Whistle Dog Tracker: What Happened, Whether Yours Still Works and What Replaced It

Whistle was a Mars Petcare brand until Tractive, a GPS-tracker maker, announced on 07/28/2025 that it had acquired it (Business Wire, "Tractive Acquires Whistle from Mars Petcare"). About a month later the Whistle service ended. Tractive's Whistle page, as archived on web.archive.org on 09/03/2025, says that on 08/31/2025 "the Whistle platform was sunset and Whistle devices no longer work." Its FAQ adds that the Whistle app was discontinued the same day and that "Your existing Whistle device is no longer supported and has stopped functioning."

We cite the archived copy because the live page has changed. On 10/09/2026, tractive.com/en/fp/whistle no longer mentions Whistle at all; it now shows an unrelated promotion. whistle.com sends visitors to tractive.com with a permanent redirect.

Tractive gave its reason on the same archived page: "maintaining and developing two separate ecosystems - devices, apps, and software - doubles the complexity and could limit the quality of service and innovation."

A Whistle tracker can't be reactivated: there's no app and no service behind it. Here's what Tractive offered and what's left of it, per the archived FAQ (09/03/2025):

• Free Tractive device. Former Whistle owners could claim a free Tractive tracker by entering the serial number from the back of the Whistle and their email. The page offered the DOG 6 and the CAT Mini. Tractive gave 09/30/2025 as the last day of the offer. It has expired.
• Prepaid time. "Any unused time on your Whistle subscription will then be credited to your new Tractive account." Owners with more than 2 months left on 08/31/2025 paid nothing at sign-up; those with less than 2 months, or no plan, had to buy a Tractive plan and got "2 months of FREE service" added.
• Warranty. "No - your Whistle device warranty will not carry over to Tractive." The new Tractive device came with Tractive's own warranty.
• Support. "Whistle's customer support is no longer available." Tractive's Customer Experience team handles former Whistle users "via live chat (based on availability) or via the contact form."
• Tagg. The same page addressed owners of Tagg trackers ("Have a Whistle or Tagg device?").

If you missed the 09/30/2025 deadline and still had prepaid Whistle time, Tractive's support is the only place to ask; Tractive's transition article (edited 10/15/2025, read 10/14/2026) says the offer ended 09/30/2025 and that "At this time, there are no active offers for former Whistle customers."

We don't publish specs or prices for Whistle trackers: the devices stopped working on 08/31/2025, so we didn't collect them. What our records hold:

Tractive's own comparison table on the archived page shows what Whistle did and didn't do. Whistle had live GPS tracking and virtual fences with escape alerts. It also had "Licking / Itching Monitoring & Food / Drinking Tracking," which Tractive marked as unavailable on its own trackers. Whistle lacked the light and sound, the vital-signs monitoring, and the XL tracker "with 1 Month Battery" that Tractive listed for itself.

We found no CPSC recall for Whistle trackers. On 10/14/2026 I searched the saferproducts.gov recall database for "Whistle," "dog collar," "GPS tracker," and "pet tracker"; the only "Whistle" hits were unrelated products, such as toy whistles and Whistler jump starters.

For a dog, the Fi Series 3+. It's $129 at Fi, and the tracker "will only work with an active membership." The default plan is $189 a year, with $99 for 6 months and $339 for 2 years also listed (Fi billing article, edited 09/15/2026). Shipping is free on orders of $100 or more, so the first year comes to about $318 before sales tax, which varies by state. Fi lists battery as "Up to 3 months" at low activity and "Up to 2 weeks" for a dog outdoors most of the day. There's no month-to-month plan, and Fi's plans carry a 6-month minimum.

For a cat or a small dog, the Fi Mini. It's $99 plus a $9 flat shipping fee, since it falls under Fi's $100 free-shipping line, on the same $189 yearly membership, so the first year is about $297. Fi's help center gives "up to 2 months" of battery; its 08/25/2025 launch post said 3 weeks. It weighs 0.56 oz.

Fi's store catalog (api.tryfi.com, 10/14/2026) shows lower first-term prices for new buyers, $59 / $99 / $189 for the 6-month, 1-year, and 2-year plans against renewal prices of $99 / $189 / $339, plus a $20 activation fee on prepaid plans, but we could not confirm them at checkout, so our first-year totals use the renewal prices from Fi's billing article (edited 09/15/2026).

Both cost more than a Tractive in year one. They're the trackers we link to; we don't link to Tractive's store.

Tractive is the official successor and the brand Whistle owners were moved to. The Tractive DOG 6 was $47.40 on sale against $79 list on 10/09/2026, and the cheapest plan, Basic, is $108 billed once a year, with no monthly option in the US. That makes a first year of about $155, roughly half the Fi Series 3+. Our full write-up, including Tractive's 2-year warranty and what owners complain about: Tractive review. The two side by side: Tractive vs Fi.

Every current GPS dog tracker we cover, with first-year costs, is in best GPS dog collars; cat trackers are in best cat GPS trackers. If the subscription is why you're hesitating, GPS dog trackers without a subscription covers the options and what they give up.