How to change a watch battery yourself: a step-by-step guide

Yes, you can change a watch battery yourself on most quartz watches, with a few inexpensive tools and about ten minutes. The vast majority of quartz watches use a standard button cell and a removable case back, so no watchmaking skill is required. This guide walks through every step, from choosing the right opener to checking the seal, so you avoid scratching the case or disturbing the movement.

Can you change a watch battery yourself?

In most cases, yes: a common quartz watch opens without special training. The mechanism is simple, the battery is an off-the-shelf coin cell, and there is nothing to calibrate afterwards. Most quartz watches open with basic tools. The exceptions are dive watches, screw-down water-resistant cases and valuable pieces, where a professional is safer to preserve the gasket, the water resistance and any warranty.

Tools you'll need

Changing a watch battery calls for very little equipment, most of it in a cheap watch-repair kit. Set up a clear, well-lit surface and lay the watch face-down on a soft cloth so the crystal does not get scratched.

• A case knife or pry tool for snap-off backs.
• A case-back wrench with adjustable pins for screw-down backs.
• A set of precision screwdrivers for backs held by screws.
• Fine plastic or brass tweezers to handle the battery without a metal short.
• A microfibre cloth and, ideally, thin gloves to avoid fingerprints on the movement.

How to open the watch case back

The way you open the case depends on its type, and this is the trickiest step. Turn the watch over on a cloth and look at the back: smooth and press-fitted, notched around the rim, or held by tiny screws. Each type has its own technique.

Snap-off case back

A snap-off back is press-fitted and has a small lip or notch on the edge. A snap-off back lifts with a case knife: slide the blade into the notch and lever gently until it pops. Always push the blade away from your fingers to avoid a slip.

Screw-down case back

A screw-down back has evenly spaced notches all around. Fit a case-back wrench onto two or three of them and turn anticlockwise to unscrew it. A grippy rubber ball or mat can sometimes loosen a back that is not tightly sealed.

Swatch and press-fit backs

Swatch-style and some fashion watches use a very tight press-fit back with a single small notch. Support the case firmly, slide the knife into the notch and lever with steady pressure. Take your time, as these backs can feel stubborn.

Removing and replacing the battery

With the back open, locate the coin cell, usually held by a small metal tab or a clip you gently ease aside. Note which way the plus sign faces (the positive pole is normally upward and visible). Using tweezers, lift out the old battery without touching the gears.

Finding the right battery size

The size is printed on the old battery, which is the surest way to buy the correct replacement. Read the code printed on the old battery, such as SR626SW or CR2032, before you remove it. Watch batteries are standardised button cells (IEC 60086-3): each code maps to a precise diameter, height and voltage. Match the code, then fit the new cell the same way up, positive pole visible, and press the retaining tab back over it.

Resealing and water resistance

Close the back by pressing straight down until it clicks for a snap-off type, or screwing it back down for a screw-down type. Check that the gasket is seated and clean. Opening a watch breaks its water seal, so the gasket should be checked or replaced before any contact with water. Wipe the case and confirm the second hand is moving.

When to see a professional

Some watches are worth taking to a watchmaker despite the cost. A dive watch always goes to a professional, because pressure testing the seal cannot be done at home. The same applies to a valuable piece, a watch under warranty, or a back you cannot open without risking a scratch. For an everyday fashion watch, such as our discounted Ernest watches, a home change stays simple and cheap. If the strap is worn too, see how to change your watch strap.

Frequently asked questions

How long does a quartz watch battery last?

A quartz watch battery lasts two to five years on average, depending on the model and how much the movement draws. Simple three-hand watches run longer than those with extra functions such as a chronograph or backlight. A second hand that jumps in several-second steps often signals a dying battery.

How do I know which battery to buy?

The safest method is to read the reference printed on the old battery, for example SR626SW, 377 or CR2032. This standardised code gives the diameter, height and voltage. If it is unreadable, a retailer can identify the cell from the watch model or by measuring the old one.

Can I damage a watch when changing the battery?

The main risks are scratching the case while levering the back and touching the gears with a metal tool. Working on a cloth, with non-magnetic tweezers and without forcing anything, the change is harmless. The second concern is water resistance, which should be checked after any opening.

Do I need to reset the time after replacing the battery?

Yes, a quartz watch restarts at zero or a random time after the swap. Pull out the crown, set the time and date, then push it back in. On watches with a date, advance the hands to the right day rather than using the quick-set at night.

My watch will not start after the change, what should I do?

First check that the battery is the correct model, seated the right way up, and that the retaining tab touches the contact. A cell that has sat in storage may already be flat. If nothing happens, the movement may need a watchmaker's attention.

Mode Tendance, jewellery and accessories editorial team. Published 17 July 2026. Sources: IEC 60086-3 standard for button cells used in horology; watch battery cross-reference tables (SR626SW / 377, CR2032).