Why is my new watch losing time?

Four different situations produce the same complaint, and they need different responses. A watch settling in after assembly, an automatic that is simply not getting enough wrist time, a movement that has picked up a magnetic field, and a genuine fault all read on your phone as minus a few seconds. Before you contact anybody, establish which one you have.

The order below is deliberate. The first two explanations are free and account for most cases. The third takes a watchmaker ten seconds. Only the fourth is a warranty matter.

What "new" actually changes

A movement is regulated at the factory, then cased, then packed, and it may have sat in a warehouse or a display case for months before you opened the box. Three things follow from that.

Fresh lubricant is still distributing across the pivots and the escapement during the first weeks of running, and a new mainspring takes a little time to settle. Both can move a rate by a few seconds a day. That is the real content of the phrase "running in", and it is why most watchmakers will not regulate a new watch until it has run for a month.

The second change is that the watch has been static and is now on a moving arm, at your skin temperature, in your resting position at night. Factory regulation is done to an average across positions. Your particular mix of positions may sit at one end of that average.

The third is the least obvious: a watch that has been sitting unworn is at zero wind when you first strap it on, and it takes a full day of wear or a proper hand-wind to get near full. Rate measured during that first day is measured at the worst part of the power curve.

The automatic that never reaches full wind

This is the most common single cause and it is not a fault. A mechanical watch keeps its best time near full wind, and an automatic depends on your arm to stay there. Desk work, short wear hours or a loose bracelet leave it running on the weak end of the mainspring, where losing five or ten seconds a day is ordinary. If your new watch also stops overnight, that is the same problem showing its other symptom, and our answer on watches that stop overnight deals with it directly.

Rule it out before anything else. Wind the watch to full by hand, roughly 30 to 40 turns of the crown from a stop, then keep winding it fully each morning through the test week. You cannot overwind an automatic. If the loss shrinks or disappears, the movement is healthy and the problem was the power reserve. If it does not, you have removed the biggest variable from the measurement. The broader list of causes for a watch that has always run slow is in why is my watch running slow.

The seven-day measurement protocol

One morning's reading is not a rate. Position, temperature and state of wind move a mechanical watch by several seconds from one day to the next, so a single figure tells you almost nothing. Seven consecutive days does tell you something.

1. Set it against a reference. Use an internet-synced clock, not another watch and not the microwave. Set the seconds precisely with the crown pulled out so the balance is stopped, if your movement hacks.
2. Wind it fully each morning, at the same time, before you read it.
3. Read the deviation at the same time every day, to the second, and write it down as a running total rather than as a daily difference.
4. Note the overnight resting position each night, and keep it the same all week. Dial up and crown down can differ by ten seconds a day on the same watch.
5. Wear it normally otherwise. The number you want is the rate you actually get, not a laboratory result.
6. Do not reset it mid-test. Resetting destroys the measurement.
7. Divide the total deviation by seven to get the mean daily rate. The accuracy calculator does the arithmetic and shows the spread.

Our note on testing accuracy at home covers the positional test and what a timing app or a timegrapher adds, including amplitude, which is the reading that separates an adjustment from a repair.

The tolerances a new watch is actually held to

Now compare your figure with the one the maker publishes for your caliber, not with your expectations. The bands are wider than most new owners assume.

Two things to take from the table. A watch losing eight seconds a day on an affordable Japanese automatic is comfortably inside specification and nothing is wrong with it. And a COSC figure is a movement result measured before the movement went into a case, so a certified watch that runs a second or two outside the band on your wrist has not necessarily failed anything. Our guide to accuracy and chronometer standards explains what each certificate covers, and what COSC certification means covers that one in detail. If you want the plain version of what to expect, see what counts as good accuracy.

Magnetism in the first weeks

A new watch is handled more than an old one: it goes on and off the wrist, gets photographed on a laptop lid, sits on a charging pad or beside a phone with a magnetic mount. Magnetism most often makes a watch gain, sometimes by minutes a day, but a magnetized rotor or barrel adds drag instead and can make it lose.

It costs nothing to rule out. A watchmaker passes the watch over a demagnetizer for a few seconds, and many will do it while you wait for free. Do it before you start a warranty conversation, because a magnetized watch returned under warranty comes back demagnetized with a note saying no fault found. What magnets do to a watch covers the sources and the test.

When it is a genuine fault

Some patterns are not normal on a new watch at any price:

• A mean daily rate outside the manufacturer's published band after seven days of full wind, with the watch demagnetized.
• A loss that grows week by week rather than staying steady.
• A watch that runs while worn and stops when rested, which points to low amplitude.
• A rate that changed suddenly after a knock or a drop.
• Any moisture, fogging or debris visible under the crystal, which is a separate and more urgent problem.
• A power reserve well short of the published figure, measured by winding fully and leaving the watch until it stops.

Assembly faults do reach customers. A reversing wheel with the wrong lubricant, a hairspring touching the balance arms, or a rotor bearing that binds all present as poor timekeeping on a watch fresh from the box, and all of them are warranty work rather than something to live with.

Making a claim that works

Take the seven-day log with you, or attach it. A dated table of readings against a stated reference, with the resting position noted and a line saying the watch was fully wound each morning and demagnetized on a given date, is a different conversation from "it loses time". It shows a mean daily rate, it shows consistency, and it pre-empts the two easy dismissals.

Ask for regulation to the published tolerance, in those words. Inside the warranty period, which commonly runs two to five years, adjusting a watch that does not meet its own specification is normally free. Outside it, regulation is a small paid job, typically in the region of $60 to $150 in the US, before sales tax, and more or less than that elsewhere depending on local labor rates. Expect the watch to be away for several weeks, and ask for the timing result on return. The manufacturer's warranty is the contract that travels with the watch wherever you live, and whatever rights you have against the seller sit alongside it rather than replacing it: in the US those come from the retailer's own returns policy and from state law, while in many other countries a statutory guarantee applies whose length is set by national law, so check the rule where you bought. Our guide to warranties and consumer rights sets out how the two interact and what a distance purchase adds.

One last piece of perspective before you send anything back. If the watch is inside its published band and you simply want better than that, say so plainly: you are asking for an adjustment, not reporting a defect. Many watchmakers will regulate a healthy movement to within a couple of seconds a day for a modest fee, and on a well-made watch that adjustment usually holds.