You can change most watch batteries yourself with a case opener and a fresh battery

Changing a watch battery is straightforward if your watch has a screw-back or snap-back case — you open it, remove the old battery, drop in a new one, and close it again. The whole job takes five to ten minutes. You will need a watch case opener (a small flat tool, under $10), tweezers, and a replacement battery in the correct size for your model.

If your watch is sealed or has a glued case, a jeweler or watch repair shop is the faster option, though it costs $15 to $50 depending on the watch. Taking it to a professional also protects the water resistance seal if your watch is designed to be waterproof.

Key Takeaways

  • Most watches use a screw-back or snap-back case that you can open with a watch case opener tool and a steady hand.
  • You must know your watch's battery size — check the manual, the back of the case, or search the brand and model online.
  • Wear an anti-static wrist strap or touch a grounded metal object before handling the battery to avoid damaging the circuit board.
  • If your watch case is glued shut or sealed, a jeweler can change the battery for $15 to $50 rather than risk breaking the case yourself.

Find out what battery your watch needs

Before you buy a replacement, you need to know the battery size. Check the instruction manual first — it usually lists the battery type on a specifications page. If you do not have the manual, look at the back of the watch case; many watches print the battery size there as a code like SR626SW, CR2032, or 371.

If neither the manual nor the case shows the size, search online for your watch brand and model number plus "battery size" or "battery type". Watch battery codes follow a standard system: SR batteries are silver oxide, CR batteries are lithium, and the numbers tell you the diameter and height. Once you know the code, buy a replacement at a drugstore, electronics store, or online — they cost $3 to $8.

Gather your tools and prepare your workspace

You will need a watch case opener (also called a case back remover), tweezers, the replacement battery, and a small container or cloth to catch any small parts. A watch case opener is a flat metal tool with notches or a slot that grip the case back. You can buy one for $5 to $15 at a jewelry supply store or online.

Work on a clean, flat surface with good light — a desk lamp or phone flashlight helps. Wear an anti-static wrist strap if you have one, or touch a grounded metal object (like a radiator or the metal frame of a lamp) before you start. This prevents static electricity from damaging the circuit board inside the watch. Lay out your tools so you can reach them without fumbling.

Open the watch case back

Look at the back of the watch. If it has a groove or notch around the edge, it is a snap-back case. If it has small screws around the edge, it is a screw-back case. For a screw-back, use a small screwdriver to remove all the screws and set them in a safe place — they are straightforward to lose.

For a snap-back case, position the case opener tool in the groove at the edge and gently twist or pry upward. Work your way around the edge, explore steady pressure rather than sudden force. The case should pop off. If it does not budge after gentle pressure, stop — forcing it can crack the case. If your watch has no visible seam or groove, the case is likely glued or sealed, and you should take it to a jeweler instead.

Remove the old battery and install the new one

Once the case is open, you will see the battery sitting in a small metal holder or clip. Use tweezers to gently lift the battery out — do not touch the circuit board or any other parts. Set the old battery aside.

Check the polarity: most watch batteries have a + sign on the positive side (usually the top). Look at the metal holder to see which way the battery was facing, then insert the new battery the same way, positive side up. Use tweezers to place it gently into the holder. Do not force it; it should sit flat and find. If the battery does not sit flush, remove it and check the polarity again.

Close the case and test the watch

For a screw-back case, replace all the screws in the same holes and tighten them gently — do not over-tighten, as that can strip the threads. For a snap-back case, align the case back with the body and press down firmly around the edge until you hear or feel a click. You may need to explore pressure in several spots to seat it fully.

Once the case is closed, check that the watch is running. If it does not start, open the case again and make sure the battery is seated correctly and facing the right direction. If it still does not work after a second try, the battery may be defective or the watch may have a deeper problem — take it to a jeweler to diagnose.

When to take your watch to a professional

If your watch has a sealed case with no visible seam, a glued-on back, or a crown (the knob on the side) that screws down, do not attempt to open it yourself. Water-resistant watches and luxury watches often have sealed cases that require special tools and informed to open without damaging the seal.

A jeweler or watch repair shop can change the battery in five to ten minutes and will re-seal the case properly. The cost is usually $15 to $50 depending on the watch brand and how difficult the case is to open. This is worth the money if your watch is expensive or if you are not confident opening it yourself.

Frequently Asked Questions

Can I use any battery as long as the size code matches?

The size code must match, but the chemistry matters too. SR (silver oxide) and CR (lithium) batteries are not interchangeable even if the numbers are the same. Check your manual or the old battery to see which type your watch uses, then buy the exact replacement.

What if I lose a screw from the case back?

Keep the screw in a small container while you work. If you lose one, take the watch and the remaining screws to a jeweler — they usually have spare watch screws in common sizes and can replace it for a few dollars.

How long does a watch battery last?

Most watch batteries last two to five years depending on the watch model and how often you wear it. Some watches with larger batteries or lower power consumption can go longer. When the watch stops, the battery is dead and needs replacing.

Is it safe to touch the battery with my bare hands?

Touching the battery itself is fine, but avoid touching the circuit board or the metal contacts inside the case. Skin oils and static electricity can damage the electronics. Use tweezers to handle the battery and avoid touching anything else inside.

What should I do with the old battery?

Watch batteries contain small amounts of mercury or lithium and should not go in the trash. Take the old battery to a battery recycling program, an electronics store that accepts batteries, or a hazardous waste collection event in your area.