What you need to do it yourself

Replacing a watch battery yourself takes about five minutes and costs between $2 and $15 for the battery itself. You need four things: the correct replacement battery for your watch model, a small flathead screwdriver (usually 1.5 mm or smaller), a case opener tool (a thin metal wedge), and a clean, flat work surface with good light.

The battery type matters. Most watches use a coin-cell battery labeled with a code like SR626SW, SR927W, or CR2032. You find this code printed on the old battery once you open the case, or in your watch's manual. Buying the wrong size will not fit, and forcing it can damage the watch. You can buy the correct battery at drugstores, supermarkets, electronics retailers, or online — they are inexpensive and widely stocked.

A case opener tool is optional but makes the job much easier. A small flathead screwdriver works if you are careful, but a case opener (sometimes called a watch back remover) costs $3 to $8 and prevents you from slipping and scratching the watch. You do not need any special training or certification to do this yourself.

Key Takeaways

  • You need the correct battery type for your watch model, which you can find on the old battery or in your watch manual.
  • A case opener tool and small flathead screwdriver are the only tools required, and both cost less than $10.
  • The entire process takes about five minutes and costs $2 to $15 total for the battery.
  • If your watch is waterproof, you may need to replace the gasket seal when you close it, which adds $5 to $10 and a few extra minutes.
  • Jewelers and watch repair shops can do this for $15 to $30 if you prefer not to do it yourself.

Opening the watch case

Most watches have a removable back cover held on by a small notch or groove. Look at the back of your watch for a thin line running around the edge — that is where the case opens. Some watches have a small indentation or slot on one side; others have a groove all the way around.

Insert the flat edge of your screwdriver or case opener into the slot or groove and gently twist or pry upward. Do this slowly — the back will pop off suddenly once the seal breaks, and you do not want to drop it or scratch the watch. If it does not move after gentle pressure, try a different spot along the edge. Never force it; if it feels stuck, the watch may have a sealed case that requires a professional opener.

Once the back is off, set it aside in a safe place. The battery will be visible inside, usually held in a small metal clip or sitting loose in a shallow compartment. Take a photo with your phone before you touch anything — this helps you remember how it was positioned when you put the new one in.

Removing and replacing the battery

If the battery is held by a metal clip, gently lift one end of the clip with your screwdriver to release the battery. If it is loose, straightforward lift it out with your fingernail or the tip of your screwdriver. Set the old battery aside — you may need to check its code if you have not already written it down.

Before you insert the new battery, look at which side faces up. Batteries have a positive side (usually marked with a + and often shiny) and a negative side (usually marked with a − and often duller). The positive side almost always faces up toward the watch face. Insert the new battery with the positive side up, then find it under the metal clip if there is one.

Press gently on the battery to make sure it sits flat and makes contact with the metal clip. A loose battery will not power the watch. If your watch has a gasket (a thin rubber or plastic ring around the inside of the case), check that it is still in place and not cracked or dried out. If it looks damaged, you may want to have a jeweler replace it when you close the case, because a bad gasket can let moisture in.

Closing the case and testing

Align the back cover with the case opening and press down firmly and evenly around the entire edge. You should hear or feel a small click as the seal closes. Do not force it — if it does not close smoothly, the battery may be positioned wrong or the gasket may be pinched. Open it again and check.

Once the back is sealed, check that your watch is running. If it has a second hand, watch it for a few seconds to confirm it is moving. If the watch does not start, open the case again and check that the battery is making contact with the clip and that the positive side is facing up. If you installed it correctly and it still does not work, the battery may be defective or the watch may have another problem.

If your watch is waterproof, test it carefully. Splash a little water on the back to see if any leaks in. If it does, or if you disturbed the gasket, take it to a jeweler to have the seal checked. A bad seal can damage the movement inside.

When to take it to a jeweler instead

Some watches have sealed cases that cannot be opened at home without special equipment. If the back does not have a visible slot or groove, or if it does not budge after gentle pressure, it is sealed. Forcing it will damage the watch.

Waterproof watches often have gaskets that need to be replaced every time the case is opened. If your watch is rated for water resistance (usually marked as 3 ATM, 5 ATM, or higher), a jeweler should handle the replacement to may support the seal is tight. The cost is usually $15 to $30, which includes the battery and a new gasket.

Vintage or expensive watches should go to a professional. If your watch is more than 20 years old, has sentimental value, or cost more than $500, the risk of damaging it is not worth the $10 you save. A jeweler can also clean the movement while the case is open, which extends the life of the watch.

Storing extra batteries and tools

If you plan to replace batteries in multiple watches, buy a small case opener tool and keep it with your spare batteries. Batteries lose charge over time even when not in use, so only buy what you need for the next year or two. Store them in a cool, dry place away from metal objects that could short-circuit them.

Label your spare batteries with the watch model they fit, or keep a note of which code goes with which watch. This saves you time the next time a battery dies. If you have several watches, you may find that two or three different battery types cover all of them.

Frequently Asked Questions

How long does a watch battery last?

Most watch batteries last between two and five years, depending on the watch model and how often you wear it. Watches you wear every day drain the battery faster than ones you wear occasionally. If your watch stops suddenly, the battery is dead and needs replacement.

Can I use any battery that fits in the slot?

No. You must use the exact battery type specified for your watch. Using the wrong voltage or chemistry can damage the watch movement or cause the battery to leak. Always check the code on the old battery or in your manual before buying a replacement.

What if the watch still does not work after I replace the battery?

First, open the case again and check that the battery is making contact with the metal clip and that the positive side faces up. If it is positioned correctly and the watch still does not run, the battery may be defective — try a different one from a different package. If a new battery does not work, the watch movement may be broken and needs professional repair.

Do I need to replace the gasket every time I open the case?

Only if your watch is waterproof. For regular watches with no water rating, the gasket can usually be reused several times. If it looks cracked, dried out, or flattened, replace it. A jeweler can do this for $5 to $10 and may support the seal is tight.

Is it cheaper to replace the battery myself or go to a jeweler?

Doing it yourself costs $2 to $15 for the battery. A jeweler charges $15 to $30 for the same job, including labor. If your watch is waterproof or sealed, or if you are not confident opening it, the jeweler's fee is worth the protection against damage.