It’s been a good run for Whistle: the “Fitbit for dogs” that lets you track Fido’s runs, nap patterns, and even heart rate from an app. But if you’ve been relying on one of their GPS collars, you’ll need a new plan—fast. On August 31, 2025, the Whistle platform will officially go offline, and every Whistle tracker everywhere will stop reporting location, activity, or health data—permanently.

Earlier this week, Pasching, Austria–based Tractive announced it had acquired Whistle from Mars Petcare, the pet-products arm of the candy and pet-food conglomerate Mars, Inc. Tractive, founded in 2012 by former Runtastic entrepreneurs, has quietly become a global leader in GPS and health-tracking collars for pets; it surpassed €100 million in annual recurring revenue in 2024 and added resting heart‑rate and respiratory‑rate monitoring earlier this year.

Mars Petcare bought Whistle back in April 2016 for about $117 million, folding the startup’s pioneering activity monitors and GPS trackers into its portfolio of brands like Pedigree and Whiskas. But after nearly a decade under Mars, Whistle’s tech and user base will now power Tractive’s expansion in the U.S.—and Whistle itself will disappear.

What Whistle owners need to know

1. Shutdown date: August 31, 2025. On that day, your Whistle tracker goes dark—no more live tracking, no more bark alerts, no more heart‑health insights.
2. Free replacement: Whistle users can claim a complimentary Tractive tracker by September 30, 2025. You’ll need to visit Tractive’s website, register for their platform, pick a subscription plan, and enter your old tracker’s serial number.
3. Subscription transfer:
   • Over two months left on your Whistle plan? Tractive will transfer the remaining time “as is,” so you won’t face an immediate bill.
   • Less than two months on your Whistle plan? You’ll need to sign up for a new Tractive subscription, but Tractive will credit two months of free service, regardless of how much time you had left.
4. Warranty: Old Whistle warranties expire on August 31. New Tractive devices arrive with a fresh two‑year warranty.

Tractive’s Basic plan starts at $108 for one year (or $144 for two years). You get:

• Real‑time GPS location tracking
• Resting heart‑ and respiratory‑rate monitoring
• Bark tracking
• Virtual fences (geofences) and “escape” alerts
• Activity and sleep insights

Their Premium tier is $120/yr, $168/2 yrs, or $300/5 yrs, and adds:

• Worldwide cellular coverage
• Family sharing so multiple people can track your pet
• One‑year location history
• Exportable GPS‑data logs

By contrast, Whistle’s most recent plans topped out around $99 per year for basic tracking, with add‑ons for cellular range and history exports. Most longtime Whistle fans report that Tractive’s entry‑level pricing is comparable—but you’ll want to crunch the numbers if you’re eyeing longer commitments or occasional travel abroad.

Steps to make the switch

1. Head to Tractive’s migration page (link in your email or at tractive.com).
2. Create a Tractive account or log in if you already have one.
3. Select your new tracker model and subscription plan.
4. Enter your Whistle tracker’s serial number to confirm eligibility.
5. Check out (you’ll only pay if you have less than two months left on Whistle).
6. Swap collars when your Tractive device arrives—and enjoy two years of warranty protection.

Don’t wait until the last minute: late‑August tech meltdowns are never fun, and you don’t want curious kitties roaming free without geofences or road‑trip pups getting lost with no GPS ping.

Whistle burst onto the scene in 2013 with activity monitors that let dog owners quantify Fido’s fitness. It quickly raised over $25 million in venture funding, forged co‑marketing deals with PetSmart, and collaborated on veterinary‑school research into canine chronic pain and epilepsy. Its GPS‑enabled trackers followed in 2014 and evolved into the Whistle 3 and Whistle GO models, beloved by data‑minded pet parents. Now, nearly a decade later, that legacy passes to Tractive, whose CEO Michael Hurnaus calls the deal “a defining moment” that will bring “cutting‑edge wellness technology to even more pet parents.”

Change can be rough—especially when it involves your furry family member’s safety net. But with a clear deadline, generous transition offers, and a feature‑rich new home for your pet’s wellness data, this may be the smoothest tracker swap you’ll ever pull off. Mark your calendar for August 31, 2025, then claim your free Tractive replacement before September 30 to keep your best friend safe, tracked, and—most importantly—home.