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Fi Series 3+: Know When Your Dog Leaves Their Safe Zone
Peace of Mind Starts with knowing sooner. When Your Dog Wanders Beyond Their Safe Zone, Every Moment of Awareness Matters
At a Glance: What Fi Series 3+ Does for Your Dog
The hardest part of a dog escaping is often the time before anyone realizes they're gone. Fi Series 3+ is designed to shorten that gap, helping families recognize an unexpected departure and respond sooner.
Safe Zone alerts: Know when your dog may have left a familiar place.
EscapeAI: Helps distinguish ordinary walks with family from possible escapes.
Family connections: Keep the people who care for your dog connected.
Lost Mode and live GPS: Follow your dog's reported movements during a search.
Search Party and collar light: Share location information with helpers and make your dog easier to spot after dark.
Beyond escape alerts: Activity, sleep, behavior insights, Fi Intelligence, and Apple Watch integration.
Cost: During our October 2026 research, the collar was listed at $129, with membership options starting at $99 for six months. Confirm current prices and charges at checkout.
You cannot watch every gate or doorway. Fi's greatest value is helping you know sooner, so you can respond sooner.
At a Glance: What Fi Series 3+ Does for Your Dog
The hardest part of a dog escaping is often the time before anyone realizes they're gone. Fi Series 3+ is designed to shorten that gap, helping families recognize an unexpected departure and respond sooner.
Safe Zone alerts: Know when your dog may have left a familiar place.
EscapeAI: Helps distinguish ordinary walks with family from possible escapes.
Family connections: Keep the people who care for your dog connected.
Lost Mode and live GPS: Follow your dog's reported movements during a search.
Search Party and collar light: Share location information with helpers and make your dog easier to spot after dark.
Beyond escape alerts: Activity, sleep, behavior insights, Fi Intelligence, and Apple Watch integration.
Cost: During our October 2026 research, the collar was listed at $129, with membership options starting at $99 for six months. Confirm current prices and charges at checkout.
You cannot watch every gate or doorway. Fi's greatest value is helping you know sooner, so you can respond sooner.
Fi Series 3+: Why You May Not Know Your Dog Has Escaped
A dog slips out, and no one notices. The gate may still be swinging when your companion is already out of sight. Fi Series 3+ helps families become aware when their dog leaves a designated safe area, giving them an opportunity to respond sooner.
By Michael London, Founder, Companion Safety Lane · Last updated October 15, 2026
Fictional example: Mara, Jess, Dev, and Scout are imagined characters. Their afternoon shows how Fi's documented features might fit into everyday ownership. They aren't customers, and their story doesn't promise an alert, steady tracking, or a happy ending.
When a Dog Slips Out and No One Notices
At 3:15 on a Thursday afternoon in November, Mara's phone lights up on her desk downtown. It's a photo from her sister, Jess. Scout, Mara's four-year-old shepherd mix, is asleep on Jess's kitchen floor in a square of late sunlight. One ear, the one that has never decided whether to stand up, is folded the wrong way. He tucks his squeaky hedgehog under his chin.
Mara smiles the way you smile at someone you love when you're too far away to touch them. She sets the phone face-down and goes back to work. Scout came from a shelter three winters ago, and he has followed her from room to room ever since. Mara likes to say every dog needs a job. Scout decided his job was her.
That morning she dropped him at Jess's with a bag of food and the hedgehog. On her way out, she said what she always says: "The side gate sticks, so you know." She heard herself say it. She thought, It'll be fine. Right now, while that photo sits face-down on her desk, Scout is still asleep. Sometime in the next fifty minutes, that will stop being true.
The Silent Gap: Why an Escape Is Hard to Catch
A side gate makes no sound when its latch fails. There's no crash and no yelp, just a gate that didn't quite catch, swinging an inch in the breeze. That is what makes an escape so hard to catch. A dog can be three houses down, nose to the sidewalk, crossing a street he has never crossed alone, while everyone who loves him still believes he's asleep in the kitchen.
The time between a dog leaving and his family finding out is the silent gap. It might last five minutes or forty. Anyone who has lived through one knows the question that comes next: How long has he been gone?
Maybe your dog bolts at thunder. Maybe a grandchild forgets the gate. Maybe a walker, a neighbor, and a spouse all share his days, and some afternoons you honestly aren't sure who has him. No one can watch every door, every minute.
Fi Series 3+ is built for that gap. It doesn't stop a gate from opening. It tries to shorten the time before you know, so you have a reason to look sooner. And if your dog is already missing, it gives you a way to search.
How Fi Alerts You When Your Dog Leaves a Safe Zone
Long before Scout slips through the gate, Mara has already done something important. She has told Fi which places Scout is supposed to be. Her home is one. Jess's house is another. Fi uses those locations, along with information from the collar and nearby phones, to help recognize when Scout may have left without someone accompanying him.
The collar cannot see an open gate or know why a dog has wandered away. It can only interpret the information it receives. That is why setting up these trusted places carefully matters: Fi needs to know where your dog belongs before it can help you recognize when something may be wrong.
What Happened to Scout: One Possible Afternoon
The following is the fictional example introduced above. It illustrates one possible afternoon, not a documented recovery.
At 4:05, Mara's phone buzzes again. The notification says Scout has left his Safe Zone. She doesn't know when he actually left. The alert says Fi saw a possible departure, not the minute he crossed the gate. Fifty minutes have passed since the photograph, and nobody can say when Scout slipped out. That is the silent gap.
Her first thought is the easy one: they went for a walk. She calls Jess, half laughing at herself.
"He's asleep in the kitchen," Jess says. "I literally just saw him."
Then Mara hears footsteps, a door, and a pause that goes on a little too long. "Mara. The side gate is open."
Mara is across town from the one person who can walk out and look. All she can do is stay on the line and open the map. Scout's last reported spot is near the county road at the edge of Jess's neighborhood, three blocks away, where the trucks never slow down. Mara notices something that matters. The dot is not live. It says it was reported minutes ago.
She taps Start Lost Mode. The dot jumps. Then it moves. Scout isn't on the road. He's heading away from it, toward the creek path behind the elementary school, the path Jess walks him every Saturday morning.
"He's going the way he knows," Mara says. She says it to Jess, and to herself. She doesn't know that. She's looking at a dot. All she has is a direction and what she knows about her dog.
From Lost Mode, she starts a Search Party. She sends the link to Jess and her cousin Dev, who lives four streets over, and they split the area between them. "Just find him," she tells Jess, who is already apologizing about the gate. "We'll do sorry later."
The sun is almost gone when Jess reaches the creek. The reported spot sits somewhere inside a dark tangle of brush along the water. She reaches the pin and sees nothing. For a moment, that is frightening in a different way. GPS has brought her close, but close is not found.
Jess works along the edge of the brush, calling his name softly, the way Mara always says it. Across town, Mara switches on Scout's collar light from the map.
In this version of the afternoon, Jess hears the tags before she sees anything. Later, she won't be able to say whether she spotted the light first or heard him first. Scout pushes his way out from between two roots, muddy to the elbows, burrs in his tail, wearing the deeply satisfied look of a dog who has just had the best afternoon of his life. He walks straight into Jess's arms as if nothing happened.
On the video call, Scout sees Mara's face, tilts his head, and barks once: the short, bossy bark he uses when she's late with dinner.
What Scout's Story Shows
Scout's afternoon began with an open gate and ended in Jess's arms. Between those two moments, Fi helped Mara recognize that something needed attention, follow Scout's reported location, and bring the people who loved him together in a search. The technology gave them actionable information. Their knowledge of Scout and the places he loved helped them decide what to do with it.
Much of that afternoon's success began long before Scout wandered away. Mara had created a Safe Zone around Jess's home, connected the people who cared for him, and practiced using Lost Mode. When the alert came, the family already understood how to respond. Scout's reunion is a fictional example, not a prediction of what will happen during every escape, but it illustrates the value of preparing while life is ordinary.
In the end, Fi helped guide the search. Jess still had to walk along the creek, listen for Scout's tags, and call his name. That is where the technology and the human bond met: one helped point the way, and the other brought Scout home.
How Fi's Escape Alerts and Tracking Tools Work
Scout's afternoon shows how several Fi features can work together when a dog goes missing. Each serves a different purpose and depends on the collar, its connections, and the people responding. Understanding those differences can help you prepare before an ordinary afternoon becomes an emergency.
Fi Safe Zones: How Escape Alerts Work
In the Fi app, you draw Safe Zones. These are the places your dog is meant to be, like your house and yard, a sitter's home, or daycare. Fi says you can have an unlimited number. The smallest circle has a 60-foot radius, and the smallest square or polygon covers 11,309 square feet, minimums Fi sets to allow for GPS error.
When Fi recognizes that your dog may have left a Safe Zone without someone accompanying them, it can send an alert to your phone. Fi recommends drawing the boundary slightly beyond the area your dog normally uses, helping reduce unnecessary alerts caused by ordinary GPS variation near the edges. Choose a boundary that reflects your dog's surroundings and the places you want to keep an eye on. A Safe Zone works as an early-warning area rather than a physical barrier, giving you information you can act on when your dog may have wandered away.
Quick Zones for Temporary Safe Places
Not every place your dog visits is part of their everyday routine. A weekend at a cabin or a few days with relatives may call for a temporary Safe Zone. Fi's Quick Zones feature lets you create a temporary area on the Live map while your dog is away from home.
Fi describes Quick Zones that can remain active for up to seven days, with a notification before they expire. When the temporary zone ends, the usual escape-alert settings resume. This gives families a convenient way to manage temporary locations without permanently changing the Safe Zones they use at home.
How Fi Recognizes Walks and Possible Escapes
Your dog has a life beyond the front door. Morning walks, afternoons with a sitter, visits to family, and familiar trips around the neighborhood are all part of that life. Fi is designed to recognize these ordinary outings so that an expected departure feels different from a moment when your dog may have wandered away alone.
Fi uses location information and connections to family members' and caregivers' phones to help it understand when someone is accompanying your dog. When a properly connected person takes your dog beyond a Safe Zone, that connection helps Fi recognize the outing as part of their normal routine. This thoughtful feature suits households where several people share the pleasure and responsibility of caring for the same dog.
For the best experience, connect the phones of people who regularly walk or watch your dog and make sure the Fi app has the permissions it needs. If an unexpected alert appears during an ordinary outing, checking the Safe Zone and phone connections can often help explain what happened. A little preparation helps Fi use the available information better, helping your family stay connected while your dog enjoys the familiar rhythms of their day.
Fi EscapeAI: Recognizing When Your Dog May Have Wandered Away
Imagine Scout leaving Jess's yard for a walk with her beside him. Now picture the same gate opening while Jess is still inside the house. Both outings begin in the same place, but only one calls for Mara's attention. Fi's EscapeAI system is designed to help recognize that difference.
Rather than relying on a location change alone, Fi says EscapeAI considers additional information from the collar and connected devices to distinguish ordinary departures from possible escapes. The feature is designed to reduce unnecessary alerts while helping families recognize when a dog may have left unexpectedly. Fi says EscapeAI operates automatically on Series 3+ without requiring a separate setting.
For a household where family members, walkers, and sitters share a dog's care, that distinction can make alerts more meaningful. When Fi detects a possible escape, the notification gives someone a reason to check the dog's location and contact the person responsible. EscapeAI is an awareness aid, and its performance depends on the information available to the system.
Helping Family Members and Dog Sitters Stay Connected
When several people share your dog's care, Fi works best when everyone understands how the collar connects to their phone. A family member taking your dog for a walk, or a sitter watching them for the afternoon, can help Fi recognize an expected outing instead of treating every departure as a possible escape.
Fi offers three levels of account access:
View-Only: Allows a caregiver to see your dog's location on the Live map.
Restricted: Provides more limited visibility. The caregiver can access the Live tab while the collar is connected to their Fi app, but cannot freely view your dog's location when that connection is absent.
Full Access: Intended for household members or other pet parents who help manage your dog's account.
Fi recommends View-Only or Restricted access for walkers and sitters. According to Fi's caregiver guidance, connecting a caregiver's phone can improve location reports and notifications, help conserve collar battery, and let them use Lost Mode.
Before your dog spends time with someone else, help that person configure the Fi app, Bluetooth, and the required location permissions. Fi's guidance calls for Always On location access and precise location on compatible iPhones. Test the connection together while your dog is safely nearby. That small preparation helps the people who care for your dog understand what information they can see and what to do if an alert arrives.
Reading Your Dog's Location on the Fi Map
When you open Fi's map, look at both the location marker and the time of its most recent report. Together, they show where the collar was last located and how recently you received that information. A location from several minutes ago may still offer a useful lead, especially when you recognize the streets, paths, or familiar places nearby.
During an active search, Live Tracking can provide more frequent reports to help you follow your dog's movements. Read each new location alongside what you know about your dog and the surrounding area. The map shows the collar's reported position, so if the collar has come off, the location may no longer represent where your dog is. Understanding that distinction helps you use the information thoughtfully when it matters most.
How the Fi Base Helps Keep Your Dog Connected at Home
The Fi Base is more than a place to charge your dog's collar. When plugged in and connected to your home's 2.4 GHz Wi-Fi network, it provides a nearby connection that helps Fi recognize when your dog is at home. Using that connection instead of repeatedly relying on GPS and cellular service also helps conserve the collar's battery.
The Base communicates with the collar through Bluetooth, but its useful range depends on your home. Walls, floors, and other obstacles can weaken the connection, and Fi's published range estimates are not consistent across its support pages. Rather than relying on a distance printed in a specification, check the connection in the rooms and areas where your dog actually spends time. A larger or multilevel home may benefit from another Base.
How Fi Tracks Your Dog Away From Home
When your dog moves beyond the familiar connections of home, Fi can use GPS to determine the collar's location and AT&T's LTE-M cellular network to send that information to your app. These are two different steps. The collar may be able to determine its location without immediately sending it to your phone.
During everyday GPS and cellular tracking, Fi describes a normal reporting interval of approximately five minutes, with adjustable GPS reporting settings. These are not promises that a new location will arrive at an exact moment. When your dog is near a connected caregiver's phone, known Wi-Fi, or a Fi Base, the collar can use those connections instead.
Think about the places your dog regularly visits: a sitter's house, a relative's yard, or a favorite walking path. Coverage and GPS reception may differ in each location. Before relying on Fi during an escape, check its connection and location reporting in those familiar places. When you open the map, look at the timestamp beside the reported location so you understand how recent the information really is.
Traveling With Your Dog Beyond Your Usual Coverage Area
Taking your dog somewhere new is a chance to enjoy time together, whether you're visiting family, staying at a cabin, or exploring a favorite vacation spot. Before leaving, it is worth checking how Fi will stay connected in that location, particularly if your plans include crossing an international border.
Fi lists cellular tracking coverage for Series 3+ in the United States, Canada, and Mexico. Before traveling, check Fi's current coverage information for your destination, especially if you're crossing an international border. GPS helps the collar determine its location, while a supported connection sends that information to your phone. Keeping your membership active and checking the collar's connection before departure will help you know what to expect.
When Fi Alerts You That Your Dog May Have Escaped
Your phone lights up with an alert that your dog may have left a Safe Zone. Before the worry takes over, open Fi's map and check when the location was last reported. Then contact whoever may be with your dog. A family member might have taken them for a walk, or a caregiver may have left without their phone properly connected.
If you discover your dog is missing, Fi gives you three ways to help organize the search: Lost Mode for more frequent location updates, the collar light to help spot your dog when someone gets close, and Search Party to share location information with people who can help. Each tool has a different purpose, and knowing when to use it can help you respond with greater confidence.
Lost Mode: Following Your Dog's Location During a Search
When you discover your dog is missing, Fi's Lost Mode lets you follow their reported movements instead of searching without direction. Activating Lost Mode starts Live Tracking, which is designed to provide more frequent location updates than everyday tracking. You can also use Get Directions to open the last reported location in a map app, giving someone nearby a place to begin looking.
As new locations arrive, check their timestamps and look for a pattern in your dog's movements. A location reported several minutes ago may already be outdated, especially if your dog is moving quickly. GPS reception and cellular coverage can affect when updates reach you, so a location on the screen is a guide for your search, not a guarantee that your dog is still standing there.
Lost Mode uses considerably more battery than ordinary tracking. Fi estimates about two days of runtime from a full charge, but actual runtime depends on the starting charge, connections, and conditions. Keep Lost Mode active while searching, as Fi recommends; monitor the remaining battery; and use the latest location information to guide the people helping you.
The Collar Light: Helping You Spot Your Dog
Fi Series 3+ includes a built-in light that you can control remotely from the app's map. When a search brings someone close to your dog's reported location, the light may help them spot the collar among bushes, trees, or shadows, especially as daylight fades.
The light is controlled separately from Lost Mode and requires a working connection to receive the command. It also uses extra battery, so it works best when someone is already searching nearby. Like the moment Jess reaches the creek in Scout's story, it offers one more practical way to turn a promising location into a closer look.
Search Party: Bringing People Together to Find Your Dog
When your dog is missing, Fi's Search Party feature lets you share a location link from Lost Mode with family members, friends, and neighbors. Everyone who helps can follow the available location information, making it easier to coordinate where to look as new reports come in.
Fi also offers Search Party+, which can notify nearby Fi members about a missing dog. In Scout's story, Mara shares his location with Jess and Dev so each person can search a different area while working from the same information. Search Party helps turn a family's concern into a coordinated effort, bringing more people together around the shared goal of finding their dog. Once your dog is safely home, you can end the location sharing in the app.
Fi's Everyday Features: Activity, Behavior, and Apple Watch
Fi Series 3+ can also help you understand parts of your dog's day beyond their location. The collar tracks activity and identifies patterns associated with rest, barking, scratching, licking, eating, and drinking. These observations may help you recognize changes in familiar routines, especially when several people share your dog's care.
Fi Intelligence, an AI assistant in the app, offers another way to explore your dog's information, including supported behavior patterns and uploaded veterinary documents. These features provide useful context, but they do not measure every aspect of your dog's health or establish a medical diagnosis. If a change concerns you, your veterinarian can help you decide what it means.
Fi also offers Apple Watch integration, providing another convenient way to access supported information about your dog's activity and location. Available functions depend on the compatible watch, software, and current Fi app. Keep your phone's escape notifications enabled, and use the Fi phone app for emergency tracking controls unless you have confirmed that the corresponding watch functions are supported.
Keeping Your Fi Collar Ready When Your Dog Needs It
The best time to prepare for an unexpected escape is when your dog is safely at home. A charged collar, a comfortable fit, reliable connections, and properly configured alerts help Fi become a useful part of your dog's everyday safety routine.
Think of Mara getting Scout ready each morning. She checks that his collar is secure, makes sure the battery is charged enough, and confirms Jess's phone is properly connected when Scout visits her house. None of those moments feel especially important at the time. But if Scout leaves through an open gate, Mara's preparation gives Fi a better chance to provide useful information when her family needs it.
Charge on a Schedule
A collar can only help you recognize an unexpected escape while it has enough battery power to operate. Fi publishes several battery-life estimates for Series 3+, depending on how your dog spends their time:
Mostly at home or on short walks: Up to three months.
Regular time in the yard and away from home connections: Approximately four to six weeks.
Outdoors for much of the day: Up to two weeks.
These are Fi's estimates, not guaranteed runtimes. Battery life changes with GPS and cellular use, the availability of nearby connections, and how often the collar must report its location. A properly connected Fi Base can help conserve power when your dog is at home.
Choose a regular day to check the battery in the app, and recharge before it becomes low. The most useful charging routine is one that keeps the collar ready without requiring you to think about it every morning.
Fit the Collar and Test the Latch
A collar your dog wears every day should be comfortable, secure, and ready for the places their adventures take them. Fi Series 3+ comes in several sizes, so you can choose a fit for your dog's neck. Fi recommends leaving enough room to slide two fingers beneath the fastened band. That gives your dog room to move comfortably while helping the collar stay securely in place during walks, play, and everyday activity.
Fi Series 3+ is also built for the wet and messy parts of a dog's life. Its IP68 water-resistance rating protects against immersion under specified test conditions, while its IP66K rating handles exposure to powerful water jets. Together, these protections make the tracker well suited to everyday adventures involving rain, puddles, splashing, and muddy outings. Your dog can enjoy being a dog without you having to treat the tracker like a delicate electronic device.
After an especially muddy adventure or a swim, a quick cleaning and a check of the collar's fit and fastening help keep it comfortable and ready for the next outing. It's a simple part of caring for something your dog wears every day—and helps keep Fi where it belongs, with your dog.
Test Before You Need It
A quiet afternoon is a good opportunity to become familiar with Fi's search tools. Fi describes a practice exercise you can arrange with someone you trust while your dog is safely accompanied.
Ask a trusted walker to take your dog on a 30-minute walk, beginning outside the Safe Zone.
Have the walker close the Fi app on their phone, following Fi's test instructions.
From your own phone, open the Live tab and activate Lost Mode. Tell everyone involved that this is only a practice exercise.
Afterward, review the Timeline to see where the collar reported its location.
Practice near places your dog regularly visits. You'll become more familiar with the map and the information available if you ever need to organize a real search.
Pair Fi With Everyday Protections
A secure gate, a comfortable collar, and a clear understanding of who is responsible for your dog all contribute to everyday safety. When family members or sitters share their care, decide who will receive Fi alerts and who can respond. These small arrangements help everyone act with confidence.
Keep a visible ID tag on your dog's collar, and make sure their microchip registration includes your current contact information. As the American Veterinary Medical Association explains, a registered microchip gives shelters and veterinary clinics another way to reunite lost pets with their families.
Together, these habits and Fi's escape-awareness tools provide several complementary ways to look after a dog who depends on the people who love them.
What Fi Series 3+ Costs to Buy and Keep Connected
Choosing a tracker for your dog's safety also means understanding what it will cost to keep that protection available. With Fi Series 3+, you purchase the collar and maintain a paid membership for its connected GPS tracking and escape-alert features. Both belong in your budget from the beginning.
The following U.S. prices were documented during our October 2026 research:
Fi Series 3+ collar: $129.
Six-month membership: $99 per six-month term.
One-year membership: $189 per year.
Two-year membership: $339 per two-year term.
At those listed prices, the collar and membership together would cost $228 for six months, $318 for one year, or $468 for two years, before any applicable activation fee, taxes, shipping, or discounts. These are reference calculations, not guaranteed checkout totals.
Fi may offer promotional pricing or introductory benefits. Its referral-program documentation also describes circumstances in which an activation fee is waived. Before purchasing, check the full checkout breakdown to confirm whether an activation fee applies to your order and what your first payment will include.
Fi's published membership arrangements also involve activation timing, plan selection, minimum commitments, and automatic renewal. These details can affect when you are charged and how much you commit to paying. Review the current membership terms before placing your order, especially the renewal date and any cancellation requirements.
A longer membership may reduce the monthly equivalent, but it also means paying more upfront. The right plan fits your household comfortably and lets you keep the connected features you paid for.
Is Fi Series 3+ the Right Safety Tracker for Your Dog?
The most useful question isn't whether Fi has enough features. It's whether those features address the worry that brought you here. If you worry your dog has left a familiar place without anyone noticing, Fi Series 3+ is designed around that moment.
Fi may be a good fit when:
You want an alert when your dog appears to leave a trusted place unexpectedly.
Your dog spends time in a yard, with relatives, or at a sitter's home.
Several people share your dog's care and can set up their phones correctly.
Cellular coverage is dependable in the places your dog regularly visits.
Your dog will wear the collar consistently, and someone will respond when an alert arrives.
Choose the kind of protection that matters most to your dog.
Different households begin with different concerns. Companion Safety Lane offers dedicated guides to help you explore the approach that best matches yours:
Smart Boundary & Training: For families interested in teaching dogs to recognize and respect designated boundaries.
Real-Time GPS & Recovery: For pet parents whose main priority is following a missing dog's movements during an active search.
Advanced Health Monitoring: For families seeking more detailed information about a pet's health patterns.
Behavioral & Daily Routine Monitoring: For owners who want to recognize meaningful changes in everyday habits.
Fi Series 3+ remains particularly relevant when your priority is recognizing that your dog may have left a familiar place unexpectedly. Consider the cellular coverage available where your dog spends time as part of that decision.
Before deciding, picture an ordinary day with your dog. Where do they spend their time? Who takes them for walks? Who would receive an alert, and who could check on them? Would the collar stay charged and comfortably fitted?
If those everyday details work for your household, Fi deserves a closer look. Its greatest value isn't replacing your attention or your home's physical protections. It gives you another way to notice when your dog may have left without you knowing.
The Peace of Mind That Comes From Knowing Sooner
Later that night, Scout sleeps at the foot of Mara's bed with his squeaky hedgehog tucked beneath his chin. Before turning out the light, she looks at the photograph Jess sent at 3:15 once more. Scout was safe and sleeping when that picture was taken. What Mara remembers most is how quickly an ordinary afternoon changed without anyone realizing it.
She rests her hand against his side and feels the familiar rise and fall of his breathing. "You're supposed to be watching me," she whispers. "That's your job." Scout doesn't stir.
On Saturday, Mara and Jess will replace the side-gate latch and test it together. Then Mara will take Scout along the creek path he knows so well. He'll stop to investigate the same trees and familiar smells, completely unaware of how frightened everyone was when he wandered there alone.
Fi cannot prevent every escape, and no collar can promise that a missing dog will be found. What it can offer is another way for a family to notice something may be wrong. For Mara, that matters: knowing that if Scout unexpectedly leaves a place where he should be safe, she may be able to respond sooner.
Sources and References
The principal manufacturer and independent references supporting this guide are linked throughout the article. They are collected here for readers who wish to examine the original documentation.
How We Researched This Fi Series 3+ Guide
Companion Safety Lane prepared this independent decision guide using Fi's official product information, support documentation, published membership terms, and feature descriptions, along with relevant guidance from GPS.gov and the American Veterinary Medical Association.
We conducted our research in October 2026. We have not independently tested Fi Series 3+, so published battery estimates, GPS performance descriptions, EscapeAI capabilities, and other performance claims are attributed to Fi rather than presented as independently established results. Product features, prices, membership terms, and policies may change; confirm current details with the manufacturer before purchasing.
Fi Series 3+ Specification Guide
By Michael London, Founder, Companion Safety Lane. Reviewed October 15, 2026, from Fi’s own pages. This guide is not based on hands-on testing. Where we write “Fi says,” it is Fi’s claim, not our test. Prices and terms change, so confirm with Fi before you buy.
The Quick Facts
Who it’s for: Dogs only. Fi points cat owners to a different product, the Fi Mini.
What it is: A GPS and cellular collar for escape alerts, location tracking, and activity and behavior trends.
Sizes: Five, chosen by your dog’s weight.
Build: Stainless steel frame. Fi says it is rated to handle over 500 pounds of force.
Water: Tractive lists both the DOG 6 and DOG 6 XL as IP68 waterproof and dustproof. The manufacturer specifies water protection to a depth of 1.5 meters (4.9 feet) for up to 30 minutes
Battery: Fi says up to 3 months. Two weeks to three months, depending on how your dog spends the day.
Charging: Wireless, on the Fi Base.
Light: An LED light you turn on from the app.
Network: AT&T’s LTE-M network. Your own phone can use any carrier.
Collar price: $129. Promotions may lower it.
Membership: Required. Fi’s published standard renewal prices are $99 for six months, $189 for one year, and $339 for two years.
Warranty: One year, for as long as your membership stays active.
What It Does
Escape alerts. You draw Safe Zones on a map around places your dog is meant to be. Fi can alert you when it thinks your dog left one without you. Fi’s app page says “the instant.” Fi’s help pages do not say how fast an alert arrives.
Location tracking. Away from home, the collar reports a location about every five minutes. You can choose an interval from 1 to 8 minutes.
Lost Mode. If your dog is missing, it switches to live tracking.
Search Party. You can send a link to helpers so everyone sees the same map. Anyone with the link can view it, so end sharing when the search is over. Fi also offers an option that notifies nearby Fi members.
Collar light. It does not turn on by itself in Lost Mode. You switch it on from the map.
Activity and behavior trends. It records activity, sleep and rest, barking, licking, scratching, eating, and drinking. The app shows these as counts and time.
Apple Watch. The Series 3+ works with the Fi Apple Watch app. The older Series 3 does not.
Health records. The app lets you store documents, view vaccine records, send health reports, and search for vets.
Fi Intelligence. An AI helper that answers questions about your dog’s data. It is available in the U.S. only, for dogs only, one dog per chat. Fi says it is not a substitute for a veterinarian.
GPS. Fi says the Series 3+ has an enhanced antenna and claims faster, more accurate GPS than the Series 3. This is Fi’s claim, not a test result.
What It Doesn’t Do
It does not fence your dog in. Safe Zones only raise a flag.
It does not promise an alert. No alert does not mean your dog is safe.
It does not promise your dog will be found.
It does not diagnose illness.
It does not measure how much your dog eats or drinks. Fi says so directly.
It does not replace an ID tag or a registered microchip. The American Veterinary Medical Association says a microchip is not a GPS device and must be registered with current contact information.
Size and Fit
Fi’s sizing guide uses weight first:
Extra Small: under 10 pounds. Neck: 9.5 to 11 inches.
Small: 10 to 19 pounds. Neck: 10.5 to 13 inches.
Medium: 20 to 39 pounds. Neck: 12.5 to 16.5 inches.
Large: 40 to 94 pounds. Neck 15.5 to 22 inches.
Extra Large: 95 pounds and up. Neck: 20 to 31 inches.
You should be able to slide two fingers between the collar and your dog’s neck. It should be snug, but not able to slip off over the head. For a growing puppy, Fi suggests starting with a smaller size and buying new bands as he grows. Fi’s Puppy Warranty promises to swap your collar for free when your puppy is full grown. Fi sells clip-on color accessories separately.
Battery and Charging
Fi’s battery guide gives these estimates for one charge:
Mostly home or short walks: up to 3 months.
Regular yard time: 4 to 6 weeks.
Outdoors most of the day, away from home: up to 2 weeks.
Lost Mode: about 2 days on a full battery. The light uses more.
The Fi Base and Your Home
The Base sits indoors, plugged in, and needs a 2.4 GHz Wi-Fi network.
The collar charges on the Base. When the collar connects through the Base, Wi-Fi, or a phone running the Fi app, it doesn’t need to use GPS or cellular. That saves battery.
Walls, metal crates, and extra floors shorten the Base’s Bluetooth reach. A larger home or one with several levels may benefit from a second Base.
A Base can’t reach far-off pastures or fields.
Where It Works
The collar sends its location over AT&T’s LTE-M network. Fi’s coverage page says the Series 3+ has tracking in the U.S., Canada, and Mexico.
Fi’s coverage guidance says its coverage maps show general coverage only and don’t show signal strength. A map that says “covered” does not promise a good signal at your house or trail.
GPS says where the collar is. Cellular sends it to you.
Behavior and activity data are not live. Fi says they can take one to two hours to appear, and they sync only when the collar connects by Bluetooth, known Wi-Fi, or a Base, with your dog inside a Safe Zone. During walks, only steps are recorded.
What It Costs
Collar: $129 on Fi’s billing page, updated September 15, 2026.
Membership: $99, $189, or $339 for six months, one year, or two years. Fi calls these its standard renewal prices. Your first charge shows at checkout and can differ.
Example, before tax and shipping: $318 for the collar plus the one-year plan, using the standard prices. Our arithmetic.
How it starts: Activation puts you on the one-year plan. You then have seven days to switch to six months or two years.
Minimum and renewal: Every plan has a six-month minimum and renews automatically. If you cancel within 30 days after a renewal charge, Fi says you get a full refund of that charge. After that, Fi doesn't refund renewals.
Returns and Warranty
Returns: Fi’s 30-day guarantee counts from the date you buy, not the date it arrives. Ask for the return authorization early. Fi requires one, and the request must be made within the 30 days. You pay return shipping. The collar must come back clean, with all its parts.
Warranty: One year, while your membership is active. It covers defects in materials and workmanship, not chewing, accidents, spills, cosmetic damage, normal wear, or batteries.
What Fi Does Not Publish
On the pages we could reach, Fi does not list the collar’s weight, exact dimensions, battery capacity, sensor types, or antenna details. If you have a small dog, ask Fi for the weight before you order.
Before You Buy
Weigh your dog and pick the size.
Check AT&T coverage at home and where your dog goes.
Decide who else will carry the Fi app, and set up their phones with you.
Plan a charging habit.
Keep an ID tag and a registered microchip.
Read the membership and return terms before you pick a plan.
Sources
© 2026 Companion Safety Lane. All Rights Reserved.
Companion Safety Lane provides educational information to help pet parents make informed decisions and support conversations with their veterinarian.
Companion Safety Lane provides educational information to help pet parents make informed decisions and support conversations with their veterinarian.
© 2026 Companion Safety Lane. All Rights Reserved.