The Fi Series 3+ launched this spring as Fi's first collar built around on-device AI and an Apple Watch companion app. It lists at $99 with six months of membership included, which undercuts nearly every serious GPS tracker on Amazon and pushes the brand further into mainstream territory.
We pulled the live Amazon listing, cross-checked it against the Tractive XL — the category's other 4.2-star heavyweight — and read through every Series 3+ review we could find. The short version: for owners of escape-prone, active dogs, the Series 3+ is the strongest pick under $100 on Amazon right now, with caveats around early production units and connectivity that any honest review has to mention.
Fi sits in an unusual spot. It's more expensive than a basic Tile tag, cheaper than the biggest Tractive subscriptions, and the only tracker on Amazon built around a fully waterproof collar rather than a clip-on attachment. That alone changes the conversation about whether $99 is actually a premium or a bargain.
Fi New Series 3+ Smart Dog Tracker Collar [6 Month Membership Included] GPS Tracker for Dogs with Health & Behavior Monitoring, Escape Alerts, Waterproof, LED, Apple Watch Compatible (Pink, Large)
Our pick is the Fi Series 3+ at $99 with six months of membership bundled. AI escape alerts, Apple Watch integration, and a 90-day battery make it the best-equipped collar under $100 on Amazon today.
Top Picks at a Glance
| # | Product | Rating | Price | |
|---|---|---|---|---|
| 1 |
Fi New Series 3+ Smart Dog Tracker Collar [6 Month Membership Included] GPS Trac...
|
4.2 (772) | $99.00 | Check Price |
| 2 |
Tractive XL Smart Dog GPS Tracker | Live Pet Tracker with Virtual Fence | Vital...
|
4.2 (4,894) | $69.00 | Check Price |
Fi New Series 3+ Smart Dog Tracker Collar [6 Month Membership Included] GPS Tracker for Dogs with Health & Behavior Monitoring, Escape Alerts, Waterproof, LED, Apple Watch Compatible (Pink, Large)
The Series 3+ is Fi's third-generation tracker, and it's the first one the company markets as an AI collar rather than just a GPS device. It holds a 4.2-star average across 772 reviews, currently sells for $99, and ships with six months of Fi membership included — the subscription that unlocks live GPS tracking, escape alerts, and health features. After the free window, membership continues at roughly $99 per year, which keeps long-term cost competitive with Tractive.
Hardware-wise, the collar is built for dogs that actually use it. The GPS module is sealed directly into a rubberized strap rated for full submersion, not a clip-on puck that can be chewed off or lost during a swim. Battery life is the headline number: Fi advertises up to 90 days on a charge in standard mode, and reviewers routinely confirm multi-week runtime in real use. That's a significant edge over most subscription trackers, which top out around 30 days.
The Series 3+ adds several software features missing from earlier Fi hardware. Escape alerts now use AI-trained patterns instead of simple geofence breaches, so the collar tries to distinguish "dog in the yard" from "dog heading for the road." It also logs activity, sleep, and early signs of behavioral change, and the new Apple Watch app puts location pings and alerts on your wrist without opening a phone. One reviewer running a farm with a Vizsla described the escape alert as "the feature that made it worth the price" after a past incident where their dog had been missing for hours.
Reviews are honest about the rough edges. The same farm owner confirmed the unit performs as advertised, but another verified buyer described going through three units during their return window before getting one that held a steady cellular connection — a pattern consistent with a young product line still ramping up its manufacturing. Fi's customer service receives mixed feedback in the reviews, with some owners praising the response speed and others frustrated by slow replacements. For buyers, the practical takeaway is to test the collar thoroughly during Amazon's return window.
Pros
- **4.2 stars across 772 reviews** with strong endorsements from owners of escape-prone breeds like Vizslas and Australian Shepherds
- **90-day battery life** on standard mode, far longer than most subscription GPS trackers
- Six months of Fi membership bundled with the **$99** price tag — no day-one subscription cost
- Apple Watch app and AI-powered escape alerts, both new to this generation
Cons
- Multiple reviewers report receiving defective units and needing replacements during setup
- Requires an ongoing Fi membership after the free six months to keep live GPS active
Tractive XL Smart Dog GPS Tracker | Live Pet Tracker with Virtual Fence | Vital Signs Monitoring of Heart & Respiratory Rate | Up to 1-Month Battery Life | Dog Collar Attachment (Green)
The Tractive XL is the closest competitor in Amazon's pet location tracker category and the obvious reference point for any Fi review. It lists at $69 — roughly 30% cheaper than the Series 3+ — carries a 4.2-star average across 4,894 reviews, and has been on the market long enough to accumulate a much larger review pool than any current Fi product.
Tractive's strengths and weaknesses come from the same design choice: it's a clip-on tracker designed to work with a collar you already own, not a full GPS collar. That makes it flexible — it moves between dogs, harnesses, and collars — but also easier to lose and less suited to heavy swimmers or chewers. Tractive advertises live updates every 2–3 seconds in LIVE mode, unlimited range on any dog size, and a roughly 1-month battery in normal use. Fi's battery comfortably beats it.
The subscription math is where this split gets interesting. Tractive charges separately for its service — around $5 per month on the basic plan, up to $144 per year on premium tiers — with no bundled trial period at the Amazon listing price. Over two years of ownership, the total cost of a Series 3+ and a Tractive XL ends up closer than the sticker prices suggest, especially if you pick Tractive's premium plan. If you already have a collar you love and want a proven tracker with a huge review base, the Tractive XL is hard to beat. If you'd rather own the collar itself and get AI features out of the box, the Series 3+ pulls ahead.
Pros
- **4.2 stars across 4,894 reviews** — the largest review base in the category on Amazon
- **$69 hardware price**, the cheapest serious GPS tracker we could verify
- Works with any existing collar or harness, so it moves between dogs
Cons
- Clip-on design is easier to lose and less durable than a sealed collar
- Monthly subscription starts day one with no bundled free period
Who Should Buy the Fi Series 3+
The Series 3+ is the right call for owners who meet any of three criteria. First, dogs that escape — reactive runners, Vizslas, huskies, Australian Shepherds, and similar breeds whose owners describe in the reviews exactly the scenarios Fi's AI alerts are designed for. Second, dogs that spend real time in water. The sealed collar design survives submersion and heavy mud in a way that clip-on competitors simply aren't built for. Third, owners who resent short battery life. A 90-day charge cycle means you effectively charge the collar four times a year rather than monthly, which matches how most people actually maintain their dog's gear.
It's less obvious for a medium-sized, well-trained dog that stays on leash or inside a fenced yard with good cell coverage. At that point, a basic AirTag attached to an existing collar covers most of the use case, and the Tractive XL handles the rest at $30 less upfront. The Series 3+ earns its price when the dog is the kind of dog that actually needs tracking — not just the kind of dog whose owner wants peace of mind.
Is It Worth It in 2026?
At $99 with six months of membership included, the Fi Series 3+ is priced aggressively for what it is. A 90-day battery, a fully waterproof build, AI-powered escape alerts, and Apple Watch integration would have been a $200 product three years ago. The 4.2-star average reflects both the strength of the hardware and the growing pains of a new generation — some buyers clearly got defective units, and Fi's customer service responses are a mixed bag.
For the right owner — active, outdoor, escape-prone dog, or a large property — the Series 3+ is the best collar on Amazon under $100 today. For owners who mainly want a cheap, reliable tracker to pair with their existing collar, the Tractive XL at $69 is the safer buy with a much larger review base behind it. Both are 4.2-star products; the difference is what you're actually buying.
Frequently Asked Questions
Is the Fi Series 3+ worth the $99 price tag?
For owners of escape-prone, active, or water-loving dogs, yes. You get a sealed waterproof collar, a 90-day battery, AI-driven escape alerts, an Apple Watch app, and six months of Fi membership in the box — a combination no other collar under $100 on Amazon matches right now.
Does the Fi Series 3+ require a subscription?
The collar ships with six months of Fi membership included. After that, live GPS tracking, escape alerts, and advanced features require an active membership, which runs around $99 per year at the time of writing.
How long does the Fi Series 3+ battery last?
Fi advertises up to 90 days of battery life in standard mode. Real-world reviews consistently report multi-week to multi-month runtime, far longer than competing subscription trackers.
Is the Fi Series 3+ waterproof?
Yes. Unlike clip-on trackers, the Series 3+ is a sealed collar rated for full submersion, which is why it's a common recommendation for dogs that swim or live in muddy environments.
How does the Fi Series 3+ compare to the Tractive XL?
Both carry a 4.2-star Amazon rating. The Tractive XL costs about 30% less at $69 and has far more reviews (4,894 vs 772), but uses a clip-on design and shorter battery life. The Fi Series 3+ wins on battery, durability, and bundled features; Tractive XL wins on price and track record.
What's the biggest risk when buying the Fi Series 3+?
The most common complaint in negative reviews is receiving a defective unit or needing a replacement during setup. Unbox and set up the collar well inside Amazon's return window so you have time to test the cellular connection and GPS signal at the locations you actually use.
