You can replace most Timex watch batteries yourself with a battery, a small screwdriver, and about ten minutes

Timex watches use standard coin-cell batteries that you can buy at drugstores, supermarkets, and hardware stores for $3 to $8. The hardest part is opening the case back without damaging the watch. If your Timex has a screw-down case back (common on sports and diving models), you will need a case-back opener tool, which costs $5 to $15. If the case back is a straightforward snap-fit, a flathead screwdriver and steady hands are enough.

The entire job takes about ten minutes once you have the right tools and the correct battery number. You do not need to send the watch away or visit a jeweler unless the case back is stuck, the battery compartment is corroded, or you are uncomfortable working with small parts.

Key Takeaways

  • Timex watches almost always use CR2032, CR2025, or SR626SW coin-cell batteries, which you can buy at any drugstore or supermarket.
  • Snap-fit case backs open with a flathead screwdriver; screw-down case backs need a case-back opener tool to avoid stripping the grooves.
  • Write down the battery number printed inside the case back before you remove the old battery, so you buy the exact replacement.
  • If the case back is stuck, corroded, or you strip the grooves, a jeweler or watch repair shop can open it for $10 to $25.

Identify your Timex model and its battery type

Open your Timex and look at the inside of the case back. You will see a battery number printed there—usually CR2032, CR2025, SR626SW, or SR927SW. Write this number down. That is the only battery that will work in your watch.

If you cannot read the number clearly, take a photo with your phone's flashlight and zoom in. Do not guess. Buying the wrong battery wastes money and may not fit or power the watch correctly.

While the case back is off, check whether it has grooves all the way around (screw-down) or smooth edges (snap-fit). This tells you which tool you need to open it next time.

Gather the right tools and battery

For a snap-fit case back, you need a flathead screwdriver (a small one, about 1/16 inch wide) and the correct replacement battery. For a screw-down case back, you also need a case-back opener tool—a metal disc with a handle and notches that grip the grooves on the case back. You can order one online for $5 to $15, or some jewelers will lend you one.

Buy the battery at a drugstore, supermarket, pharmacy, or hardware store. Ask for the battery number you wrote down. If the store does not have it in stock, they can usually order it for you within a day or two. Online retailers ship them quickly as well.

Open a snap-fit case back

Place the watch face-down on a soft cloth or towel so you do not scratch the crystal. Find the small slot or notch on the edge of the case back—most Timex snap-fit backs have one or two.

Insert the flathead screwdriver gently into the slot and twist or pry slightly. The case back should pop off. If it does not move after light pressure, try a different slot or rotate the watch slightly and try again. Do not force it—if you feel strong resistance, stop and try a different approach.

Once the case back is off, set it aside in a safe place. The battery sits in a small metal holder or clip inside.

Open a screw-down case back

Place the watch face-down on a soft cloth. Grip the case-back opener tool so the notches align with the grooves on the case back. Turn the tool counterclockwise (lefty-loosey) slowly and steadily. The case back will unscrew after a few turns.

If the case back is very tight, wrap a rubber band around the tool handle for better grip, or ask someone else to hold the watch steady while you turn. Do not force it—if you feel the tool slipping, stop and reposition it so the notches sit fully in the grooves.

Once the case back is loose, unscrew it by hand the rest of the way. Set it down carefully so you do not lose the rubber gasket (a thin ring) that sits inside the grooves. You will need to put it back when you close the watch.

Remove the old battery and install the new one

Look at how the old battery sits in its holder. Most Timex watches have a small metal clip or spring that holds the battery in place. The positive side (marked with a + or the flat side) usually faces up.

Gently lift or slide the old battery out. If it is stuck, use a plastic spoon handle or a plastic tweezers to pry it up—never use a metal tool that could scratch the inside of the watch. Dispose of the old battery according to your local rules. Many drugstores and supermarkets have battery recycling bins.

Insert the new battery with the positive side facing the same direction as the old one. Make sure the metal clip or spring holds it firmly in place. The battery should not rattle or move when you gently shake the watch.

Close the case back and test the watch

For a snap-fit case back, align the case back with the watch body and press down firmly until you hear or feel a click. The back should sit flush with the case—no gaps or edges sticking out.

For a screw-down case back, make sure the rubber gasket is sitting in the grooves. Screw the case back on by hand first, then use the case-back opener tool to tighten it. Turn clockwise (righty-tighty) until it is snug, but do not over-tighten—you will strip the grooves or crack the gasket.

Turn the watch over and check that it is running. The second hand should be moving. If the watch does not start, open the case back again and make sure the battery is seated firmly in its holder and facing the right direction.

When to take your Timex to a professional

If the case back is stuck and will not budge after gentle pressure, a jeweler or watch repair shop can open it without damage. This usually costs $10 to $25. Do not force a stuck case back yourself—you risk cracking the crystal or stripping the grooves.

If you see corrosion (green or white crusty deposits) inside the case back or around the battery holder, the watch may have water damage. A professional can clean the corrosion and check whether the movement is still working. If the watch has been sitting for years, the battery compartment may be corroded even if the watch looks fine from the outside.

If you are uncomfortable working with small parts or do not have the right tools, a jeweler can replace the battery for you in a few minutes. The cost is usually $15 to $30, which is worth it if you would rather not risk damaging the watch.

Frequently Asked Questions

Can I use a different battery if my Timex battery number is not in stock?

No. Different coin-cell batteries have different voltages and sizes. A CR2032 and a CR2025 look similar but are not interchangeable. Using the wrong battery can damage the watch movement or cause it to run fast or slow. Wait for the correct battery or order it online.

How long does a Timex watch battery last?

Most Timex watch batteries last two to five years, depending on the model and how often you use features like the backlight or alarm. Batteries in watches you wear every day may last closer to two years. Batteries in watches you wear occasionally may last five years or longer.

What if the watch still does not work after I put in a new battery?

First, open the case back again and make sure the battery is seated firmly and facing the right direction (positive side up, usually). If it is, try a different new battery to rule out a defective one. If the watch still does not work, the movement may be damaged or the battery contacts may be corroded. A jeweler can diagnose the problem.

Do I need to replace the rubber gasket when I close a screw-down case back?

No, the gasket stays in place inside the grooves. Just make sure it is sitting flat and not twisted before you screw the case back on. If the gasket is cracked, dried out, or missing, the watch will not be water-resistant. A jeweler can replace it for a few dollars.

Is it safe to open a Timex watch myself if it is water-resistant?

Yes, as long as you close it correctly. The rubber gasket is what keeps water out, not the case back itself. As long as you seat the gasket properly and screw the case back on snugly (not over-tight), the watch will remain water-resistant. If you are unsure, a jeweler can do it for you.