We research products independently. When you buy through links on this page, we may earn a commission from Amazon at no extra cost to you. As an Amazon Associate we earn from qualifying purchases. Read our affiliate disclosure.
If your automatic watch stopped working, the most likely cause is simply that it ran out of power. An automatic winds only while it moves, and most entry movements run about 40 hours once you take them off. Give the crown 20 to 40 turns (or swirl the watch if it cannot hand-wind), set the time, and wear it. If it keeps running, nothing is wrong. If it stops again within hours while fully wound, the movement has a fault that needs a watchmaker.
Below is a quick diagnosis, step by step, followed by the real faults and what each one means.
Quick diagnosis
| What happens | Likely cause | What to do |
|---|---|---|
| Stopped after a day or two off the wrist | Power reserve ran out | Wind, set, wear |
| Stops overnight after a day of wear | Not enough wind from light activity | Hand-wind in the morning or use a winder |
| Runs fast by minutes a day, then erratic | Magnetism | Demagnetize |
| Starts when shaken, stops soon after while fully wound | Dirty or dry oil, or wear | Service |
| Will not start at all after winding | Broken mainspring or balance staff, or a jam | Watchmaker |
| Stopped after a drop or knock | Damaged balance staff or shock jewel | Watchmaker |
| Crown spins freely, nothing winds | Broken stem or winding mechanism | Watchmaker |
| Moisture under the crystal | Water entry | Watchmaker immediately |
Step by step: how to restart an automatic watch
- Unscrew the crown if it is a screw-down crown (most dive watches).
- Wind it by hand. With the crown pushed in, turn it clockwise 20 to 40 times. If your movement does not hand-wind (for example, Seiko's older 7S26), hold the watch dial up and swirl it gently side to side for a minute.
- Watch the seconds hand. It should start within a few turns.
- Set the date and time, passing midnight and avoiding the 9 p.m. to 3 a.m. date-change window. Our guide on how to set an automatic watch has the full method.
- Screw the crown back down if needed.
- Wear it normally for a day and note when you take it off.
- Check how long it runs off the wrist. If it lasts roughly its rated reserve, it is healthy.
For more on winding, see how to wind an automatic watch.
The common causes, explained
1. The power reserve ran out
This is normal behavior, not a fault. Seiko's 4R and Orient's F6 movements run about 40 to 41 hours fully wound; Tissot's Powermatic 80 runs 80 hours. Take a 40-hour watch off on Friday evening and it will be stopped by Sunday. Our automatic watch power reserve guide explains how reserve is measured and why a watch's real reserve can be shorter than the rated figure.
2. Not enough wind during the day
A self-winding watch depends on movement. A day at a desk, or wearing it loosely on a wrist that barely moves, may not wind the mainspring fully, so the watch stops overnight. Fixes:
- hand-wind it each morning you put it on;
- wear it a little more snugly, so the rotor moves with your wrist;
- keep it on a winder at night, set to the published turns per day and direction for the movement; see our watch winder settings lookup.
3. Magnetism
Magnetism usually makes a watch run fast rather than stop, but a strongly magnetized hairspring can make the rate erratic or stop the watch. If it started gaining minutes a day before stopping, test it with a compass and demagnetize it; see how to demagnetize a watch.
4. Dried oil and dirt
Lubricants thicken and dry over years. The watch loses amplitude, keeps poor time and eventually stops even when wound. Shaking may restart it briefly. This is the classic sign that a service is overdue. Makers publish recommended intervals; see how often to service an automatic watch.
5. A broken mainspring
If the crown turns with no resistance and the watch will not start, or it starts and stops immediately, the mainspring may be broken. It is a routine repair for a watchmaker.
6. Shock damage
A drop onto a hard floor can break a balance staff (the axle of the balance wheel) or dislodge a shock jewel. Symptoms include a watch that will not run at all, or runs only in certain positions. Do not keep winding it; take it in.
7. Water entry
Moisture or fog under the crystal means water got in, often through a crown left unscrewed or aged gaskets. Water causes rust quickly. Take the watch to a watchmaker as soon as possible and do not keep wearing it.
8. Crown, stem or setting problems
A crown that spins without winding, will not pull out, or comes out in your hand points to a stem or keyless-works problem. It is a repair, not a home fix.
Automatic watch not keeping time
A watch that runs but keeps bad time is a related problem. Large, sudden gains usually mean magnetism. Steady losses that get worse toward the end of the day often mean the mainspring is running low, so the watch needs more wind. Slow drift over years, with a shorter reserve than before, points to aging oil and a service. Our guide to an automatic watch running fast goes through the causes and what counts as normal accuracy for common movements.
Things not to do
- Do not open the case unless you are trained; dust and fingerprints cause more problems.
- Do not shake it violently to restart it.
- Do not force the crown if it feels stuck.
- Do not keep running a watch with water inside.
- Do not set the date between about 9 p.m. and 3 a.m.
- Do not assume a winder will fix it. A winder solves low wind, nothing else. If the winder itself has stopped turning, see our watch winder troubleshooting guide.
When it is time for a watchmaker
See a watchmaker if, after a full hand-wind, the watch:
- stops again within a few hours;
- runs only in certain positions;
- keeps erratic time even after demagnetizing;
- shows moisture, rattles or has a loose rotor;
- was dropped and has not run right since.
A good independent watchmaker can diagnose most of these quickly. For a branded watch under warranty, contact the maker or an authorized service center first.
How to keep it from stopping
- Wear it daily, or rotate with a plan.
- Hand-wind it on mornings you put it on after a day or more off.
- Choose a longer power reserve next time if you rotate watches.
- Use a winder at the movement's published settings if you want it ready to go.
- Keep it away from magnets and service it at the maker's interval.
FAQ
Why did my automatic watch stop?
Almost always because it ran out of power reserve. An automatic only winds while it moves, and most entry movements run about 40 hours off the wrist. Wind it by hand (or swirl it, if it cannot hand-wind), set it and see if it keeps running. If it stops again within hours while fully wound, there is a mechanical fault.
Why does my automatic watch stop overnight?
Because it was not wound enough during the day. Light activity, such as a day at a desk, may not wind the mainspring fully. Hand-wind it in the morning, wear it longer, or use a winder at the movement's published turns per day.
Can a watch winder fix an automatic watch that keeps stopping?
Only if the cause is low wind. A winder keeps the mainspring topped up. It does not fix a broken mainspring, a damaged balance, magnetism or dried oil. If the watch stops on a winder set correctly, see a watchmaker.
Is it bad to let an automatic watch stop?
No. Letting an automatic run down is normal and does not damage it. You just need to wind it and reset the time and date when you pick it up, ideally setting the date outside the 9 p.m. to 3 a.m. window.
How much does it cost to fix an automatic watch that stopped?
It depends on the cause and the watch. Demagnetizing is quick and inexpensive; a full service costs more and varies by brand and movement. Ask a watchmaker for an estimate, and see our guide on how often to service an automatic watch.