You can change most watch batteries at home with a small tool kit and 10 minutes

Changing a watch battery is straightforward if your watch has a removable back. You need a case opener (a flat tool that pries the back off), a small screwdriver that fits the battery compartment screws, tweezers to handle the battery without touching its surface, and a replacement battery in the correct size for your model. The whole job takes about 10 minutes. If your watch is sealed or glued shut, or if you are uncomfortable working with small parts, a jeweler or watch repair shop will do it for $10 to $30 including the battery.

The first step is finding out what battery your watch uses. Look inside the back cover or in your watch manual for a code like SR626, LR44, or 371. If you cannot find it, a jeweler can identify the battery by looking at your watch. Once you have the code, you can buy the replacement battery online or at a pharmacy, drugstore, or electronics retailer for $3 to $8.

Key Takeaways

  • Most watch batteries are identified by a code printed inside the case back, such as SR626 or LR44, and cost $3 to $8 to replace.
  • You need only four tools: a case opener, a small screwdriver, tweezers, and the correct replacement battery.
  • The battery sits in a metal holder that you must remove and reposition when you install the new one, or the watch will not make contact.
  • If your watch back is sealed, glued, or difficult to open, a jeweler can change the battery for $10 to $30 rather than risk damaging the case.

Opening the watch case back

The case back is usually held on by a small notch or groove that runs around the edge. A case opener is a flat metal tool with a small blade that fits into that groove. You can buy one for $5 to $15 at a jewelry supply store or online. Place the watch face-down on a soft cloth so the crystal does not scratch, then position the case opener blade into the groove at the edge of the back.

Turn the case opener counterclockwise, as if you were unscrewing a jar lid. The back should pop off. If it does not move after a quarter turn, stop and try a different spot on the groove — sometimes one side is easier than the other. Do not force it, because the blade can slip and scratch the case. If the back will not budge after trying two or three spots, the case may be glued or sealed, and you should take it to a jeweler instead.

Removing and replacing the battery

Once the back is off, you will see the battery sitting in a metal holder or clip. The holder usually has a small tab or arm that you can lift with a fingernail or the tip of a screwdriver to release the battery. Lift that tab gently and the old battery will come free. Set it aside — do not throw it away yet, because you need to confirm the code matches your replacement.

Before you install the new battery, check the code on the old one. It should match the code on the new battery package. If it does not, you have the wrong size and should not force it in. Once you have confirmed the match, use tweezers to pick up the new battery by its edges only — never touch the flat surfaces, because skin oils can reduce how well it makes contact inside the watch. Place the battery into the holder with the positive side (usually marked with a + or the shiny side) facing up, then press the metal tab back down to hold it in place.

Closing the case and testing

Before you seal the back, hold the watch to your ear and listen for a ticking sound. If you hear it, the battery is making contact and the watch is working. If you hear nothing, the battery may not be seated properly. Lift the metal tab again, remove the battery with tweezers, and reposition it so the positive side is facing up and the battery sits flat in the holder. Then press the tab down again and listen.

Once you hear ticking, place the case back on the watch with the notch or groove aligned with the case opener blade. Turn the case opener clockwise (as if tightening a jar lid) until you feel resistance. Do not overtighten — a quarter turn past snug is enough. The back should sit flush with the case with no gap. If there is a gap, the back is not seated correctly and may come loose. Remove it and try again, making sure the notch is fully aligned before you turn the opener.

What to do if the battery does not work

If the watch still does not tick after you have reseated the battery twice, the problem is usually one of three things: the battery is installed upside down, the metal tab is not making firm contact with the battery, or the old battery was dead and you bought the wrong replacement code by mistake.

Check the battery code one more time against the package. If the codes do not match, the battery is the wrong size and will not work. Return it and buy the correct one. If the codes match, remove the battery again and look at the metal tab — it should be clean and shiny. If it looks dark or corroded, wipe it gently with a dry cloth. Then reinstall the battery with the positive side facing up, press the tab down firmly, and listen again.

When to take your watch to a jeweler instead

Some watches have case backs that are glued or sealed rather than screwed on. You can usually tell by looking at the edge — if there is no visible groove or notch, the back is probably glued. Trying to pry it open can crack the case or damage the crystal. If you are not sure, ask a jeweler to look at it first.

Watches with screw-down case backs (common on dive watches and sports models) require a special wrench tool rather than a case opener. If your watch has small notches around the entire back edge instead of a groove, it has a screw-down back. A jeweler has the right tool and can open it without stripping the notches.

Frequently Asked Questions

How do I know what battery my watch needs?

Look inside the case back for a printed code like SR626, LR44, or 371. If you cannot find a code, take the watch to a jeweler and they will identify it by looking at the old battery. Once you have the code, you can buy the replacement online or at a pharmacy.

Can I use any battery that fits in the space?

No. The code tells you the exact voltage and size your watch needs. Using the wrong battery can damage the movement or cause the watch to run too fast or slow. Always match the code on the old battery to the new one before you install it.

What if I touch the battery with my fingers?

Skin oils can reduce contact between the battery and the metal tab, which may cause the watch to stop working or work intermittently. If you touch it, wipe it gently with a clean, dry cloth before you install it. Using tweezers to handle the battery by its edges is the safest approach.

How long does a new watch battery last?

Most watch batteries last between one and three years, depending on the watch model and how often you wear it. Watches you wear daily typically use the battery faster than ones you wear occasionally. The battery code sometimes indicates the expected life span.

Should I replace the gasket or seal when I change the battery?

If your watch is water-resistant, there may be a rubber gasket or seal around the case back. If you removed the back and it looks cracked or dried out, a jeweler should replace it when they change the battery. If it looks intact, you can reuse it. Do not reuse a gasket that is visibly damaged, because it will not keep water out.