TAG Heuer · TAG Heuer TH31

TAG Heuer Aquaracer Professional 300 and Carrera Day-Date power reserve: inside the TH31

The current TAG Heuer Aquaracer Professional 300 Date and GMT, the Carrera Day-Date and the Carrera Twin-Time all run on the TH31 family. A full wind lasts about 80 hours, or three and a third days.

Updated September 2026 · Based on manufacturer specs, published reviews and watchmaker/owner reports

Watches that use the TH31

TH31 is TAG Heuer's name for a family of time-only automatic movements made for it by AMT, the high-end custom-movement arm of Sellita. It replaced the 38-hour Calibre 5 in the Aquaracer Professional 300 and is spreading through the Carrera's non-chronograph models. The suffix tells you the version: TH31-00 for time and date, TH31-02 for day-date, TH31-03 for a caller GMT.

Not every modern TAG Heuer time-only watch has a TH31. The titanium Aquaracer Professional 500 Date and the Aquaracer Professional 1000 Superdiver use the Kenissi-made TH30-00, which has a 70-hour reserve. Aquaracer Professional 200 models in steel and steel-and-gold have used the Calibre 5. Check the reference or the case back if it matters to you.

Specs at a glance

History and where it came from

For two decades most time-only TAG Heuers ran on the Calibre 5, a lightly modified ETA 2824 or Sellita SW200 with about 38 hours of reserve. It was reliable and cheap to service, but by the 2020s it looked short on reserve next to rivals like the Powermatic 80 and Tudor's in-house calibres.

TAG Heuer's answer came from two directions. In 2022 it launched the TH30-00, made by Kenissi, in the Aquaracer Superdiver. Then at Watches and Wonders 2023 it introduced the TH31-00 in two solid-gold Aquaracer Professional 200s. Fratello reported that the movement was co-developed with Manufacture AMT, Sellita's department for high-end and custom movements in La Chaux-de-Fonds, and that AMT produces and assembles it exclusively for TAG Heuer. It's one of the movements developed under TAG Heuer's movements director, Carole Forestier.

The TH31-00 has 30 jewels, Côtes de Genève on the bridges and a rotor shaped around the TAG Heuer shield. More usefully, it has 80 hours of reserve at 4 Hz, more than double the Calibre 5, while keeping the faster beat rather than slowing to 3 Hz as the Powermatic 80 does.

In 2024 TAG moved it into the watch that matters most for sales: the steel Aquaracer Professional 300 Date, which shrank from 43 to 42 mm and got a COSC certificate. The GMT model got the TH31-03. In 2025 the Carrera Day-Date (TH31-02) and Carrera Date Twin-Time (TH31-03) followed, this time without chronometer certification.

Accuracy in the real world

For the Aquaracer Professional 300 Date and GMT, the reference point is COSC: -4/+6 seconds a day, tested on the uncased movement over 15 days in several positions and temperatures. That's a real step up from the Calibre 5, which had no accuracy promise at all. The "Chronometer" line on the Aquaracer dial isn't decoration.

The Carrera Day-Date and Twin-Time don't carry a certificate, and TAG Heuer doesn't publish a tolerance for them. It's the same basic movement, so there's no reason to expect it to be poor, but you shouldn't expect COSC-level results from every example either. If a new Carrera runs well outside ten seconds a day, it's worth raising under warranty.

TH31s haven't been on the market long enough for a large body of long-term owner data, and the published reviews we read didn't report measured rates. Treat the COSC figure as the benchmark for the Aquaracer and judge a Carrera by how it runs in its first months.

Reliability and servicing

• Warranty. TAG Heuer gives five years on watches with the TH31, which covers most of the period when a new movement's teething problems would show up.
• Brand service. This is an exclusive movement, not an off-the-shelf SW200, so parts go through TAG Heuer. Plan on brand service or an independent with TAG Heuer parts access.
• It's young. The TH31 has been in production since 2023. The Sellita-based industrial background is reassuring, but there isn't a decade of service history yet the way there is for the Calibre 5.

Quirks worth knowing

• Which TH31 do you have? Two watches with "TH31-03" on the spec sheet differ: the Aquaracer GMT's is COSC-certified and the Carrera Twin-Time's isn't.
• It's a caller GMT. In the TH31-03 the 24-hour hand jumps independently, not the local hour hand. That keeps a quick-set date, but frequent flyers who want to jump the hour hand when they land will find it less convenient.
• The day and date on the Carrera Day-Date are both set through the crown. As with most day-date movements, avoid changing them late in the evening, when the change mechanism is engaged. Here's why.
• Screw-down crown on the Aquaracer. Unscrew it before winding or setting, and screw it back before swimming.
• A lot of spring to fill. An 80-hour mainspring takes a lot of winding. From stopped, don't rely on a desk day to fill it before a weekend off.

How it compares

• TAG Heuer Calibre 5: the Sellita SW200 or ETA 2824 it replaced. Easy to service anywhere, but only about 38 hours.
• TAG Heuer Heuer 02: TAG's in-house chronograph movement, with the same 80-hour reserve, in the Carrera Chronograph and Monaco.
• Powermatic 80: the same 80 hours, but at a slower 3 Hz and without a COSC certificate in most versions.
• Sellita SW200-1: the industrial movement from the same supplier, with less than half the reserve.
• Rolex 3235: a 70-hour, 4 Hz date movement tested to -2/+2 s/day, at a much higher price.
• Rolex 4131 and Hamilton H-51: both chronographs, but useful benchmarks for reserve: 72 hours for the Daytona and 60 hours for the hand-wound Intra-Matic Chronograph H.

Living with the 80-hour reserve

Eighty hours is three and a third days. Take a fully wound Aquaracer Professional 300 off at 6pm on Friday and it's still running at 2am on Tuesday. The old Calibre 5 Aquaracer would have stopped on Sunday morning. That's the biggest practical change for anyone who swaps watches at the weekend.

The catch is getting it full. A Carrera Day-Date worn to the office for a quiet day may go into the weekend well short of 80 hours, and a stopped day-date is the most annoying kind to reset. Give it a good hand wind before you put it away if you want it running on Monday, and don't expect it to survive a week-long holiday with your diver. Watch Winder counts down this 80-hour reserve for each watch you own and reminds you before it stops. To check a particular weekend, try the "Will my watch stop?" calculator.

Verdict

The TH31 fixes the one thing that held back TAG Heuer's everyday watches: reserve. It keeps a 4 Hz beat, adds 80 hours and, in the Aquaracer, a COSC certificate and a five-year warranty. The trade-off is that it's exclusive, so servicing goes through TAG Heuer rather than any corner watchmaker, and it's still new. If you're choosing between an older Calibre 5 Aquaracer and a TH31 model, the TH31 is the one to get. For the Carrera Day-Date, the new movement is the best reason to choose the current version over an older one.

FAQ

How long does a TAG Heuer Aquaracer Professional 300 run off the wrist?

The 2024 and later Aquaracer Professional 300 Date and GMT, with the TH31, run for about 80 hours from a full wind. Older versions with the Calibre 5 manage about 38 hours.

What is the power reserve of the TAG Heuer Carrera Day-Date?

The 2025 Carrera Day-Date, with the TH31-02, runs about 80 hours from full. Earlier Carrera Day-Date models used older movements, so check the reference or the year.

Is the TAG Heuer Aquaracer 300 Date a chronometer?

Yes. The TH31-00 in the current Aquaracer Professional 300 Date is COSC-certified to -4/+6 seconds a day.

Is the TH31 an in-house movement?

Not entirely. TAG Heuer co-developed it with AMT, Sellita's high-end division, which makes it exclusively for TAG Heuer. It's a proprietary movement, not a stock Sellita.

Is the Carrera Day-Date's TH31 COSC-certified?

No. The TH31-02 in the Carrera Day-Date and the TH31-03 in the Carrera Twin-Time aren't chronometer-certified, unlike the Aquaracer's movements.

What's the difference between TH31-00, TH31-02 and TH31-03?

TH31-00 shows time and date, TH31-02 adds the day, and TH31-03 adds a caller GMT hand. All three have an 80-hour reserve and beat at 4 Hz.

Why did my TAG Heuer Aquaracer stop after a day and a half?

If it's an older model, it probably has the 38-hour Calibre 5. If it has the TH31, it most likely wasn't fully wound; give it a good wind by the crown before a break.

Sources

• Monochrome: TAG Heuer updates the Aquaracer Professional 300 Date and GMT
• Monochrome: TAG Heuer refreshes its Carrera Day-Date and Carrera Twin-Time
• Fratello: TAG Heuer adds precious metal to the Aquaracer Professional 200 series (TH31-00 debut)
• Fratello: Introducing the TAG Heuer Carrera Day-Date
• aBlogtoWatch: TAG Heuer Aquaracer Professional 300 Date and GMT review

Keeping it running

• On an average day an automatic gains roughly 4 hours of reserve per hour on the wrist, so about 20 hours of wear fills the TAG Heuer TH31. Desk days charge more slowly.
• Most automatics can also be wound by the crown. If yours has stopped, a few dozen turns gets it going before you put it on.
• Off the wrist it stops about 80 hours after it was last full.
• If it does stop, don't set the date between 9pm and 3am. Here's why.

Never let it stop

Watch Winder counts down the reserve of every watch you own and reminds you before one stops. It already knows the TAG Heuer TH31: type your watch's name and the reserve fills itself in.

Manufacturer's published figure. Real reserve varies with the watch's age and service; check your manual.