You can change most watch batteries yourself with basic tools and a few minutes of time

Changing a watch battery is straightforward if your watch has a removable case back. You'll need a small screwdriver (usually Phillips head), a case opener tool (optional but helpful), and a replacement battery in the correct size for your model. The whole process takes five to ten minutes. If your watch is sealed or has a screw-down case back, you may need a jeweler or watch repair shop instead — attempting it yourself risks damaging the waterproofing.

The most important step is finding out what battery your watch uses. Look inside the case back or check your watch manual for the battery model number, which typically looks like SR626SW, CR2032, or LR44. Once you know the number, you can buy a replacement at a drugstore, electronics retailer, or online for between $3 and $15.

Key Takeaways

  • Most watches have a removable case back held on by three to six small screws that you can open with a Phillips screwdriver.
  • The battery model number is printed inside the case back or in your watch manual, and you need this exact number to buy the right replacement.
  • Batteries cost $3 to $15 and are sold at drugstores, electronics shops, and online retailers.
  • If your watch has a screw-down case back or is marked water-resistant, a jeweler can change it for $10 to $30 to avoid damaging the seal.

Identifying your watch battery type

Before you buy anything, you need to know which battery your watch uses. Open the case back (see the next section) and look at the battery itself — the model number is stamped or printed on the top. Common numbers include SR626SW (silver oxide), CR2032 (lithium coin cell), and LR44 (alkaline). Write down the exact number.

If you can't open the case back or the number is worn away, check your watch manual or the manufacturer's website. You can also search "[watch brand] [watch model] battery" online, and most results will list the correct type. Take a photo of your watch and bring it to a drugstore pharmacy or electronics counter — staff can often identify the battery by sight.

Opening the case back without damage

Most watch case backs are held on by three to six small screws arranged in a circle. Look for a small slot or indentation on the edge of the case back where a screwdriver fits. Use a Phillips head screwdriver that matches the slot size — too large and you'll strip the screw head; too small and you won't get grip. Turn slowly and steadily counterclockwise.

As you remove each screw, place it somewhere you won't lose it — a small dish or piece of tape works well. Once all screws are out, gently pry the case back off with your fingernail or a plastic case opener tool. Avoid using a metal knife or screwdriver to pry, as this can scratch the watch. If the case back won't budge, check that all screws are fully removed and try again — don't force it.

Some watches have a snap-on case back with no screws. These pop off with gentle pressure from a case opener tool or the edge of a coin, but require more care not to damage the seal. If you're unsure whether your watch is screw-on or snap-on, check the manual or search for your model online before attempting to open it.

Removing the old battery and installing the new one

Once the case back is open, you'll see the battery sitting in a small metal holder or clip. Note which side is facing up — the positive (+) side usually faces outward. Gently lift or slide the battery out. If it's stuck, use a plastic tweezers or the edge of a plastic spoon to nudge it free. Avoid touching the battery with your bare fingers, as oils can affect its performance.

Before inserting the new battery, check that it matches the number you wrote down. Place it in the holder with the positive side facing the same direction as the old one. Press down gently until it clicks or sits flush in the clip. The battery should not require force — if it doesn't fit easily, you may have the wrong size.

Closing the case back and testing

Once the new battery is in place, carefully align the case back with the watch body. The screw holes should line up. Insert each screw by hand first to avoid cross-threading, then tighten with your screwdriver in a clockwise direction. Tighten firmly but not so hard that you strip the screw — you should feel resistance, not a grinding sensation.

After closing the case back, check that the watch is running. If it doesn't start, open the case back again and make sure the battery is seated properly and facing the right direction. If the watch still doesn't work after a second attempt, the battery may be defective or your watch may need professional repair.

When to take your watch to a professional

Some watches should not be opened at home. If your watch is marked "water-resistant," "water-proof," or "diving watch," the case back is sealed with a gasket that keeps water out. Opening it yourself can damage the seal, and the watch may leak the next time you wear it near water. A jeweler or watch repair shop can replace the battery and reseal the case for $10 to $30.

Watches with screw-down case backs (where the entire back twists off like a jar lid) are also best left to professionals unless you have the right tools. Vintage watches, luxury watches, or any watch you're unsure about should go to a professional. The cost of a repair is usually less than the cost of damage from a mistake.

Frequently Asked Questions

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 quartz watches with fewer features can run for seven to ten years on a single battery. If your watch stops suddenly after only a few months, the battery may be defective or your watch may have a different problem.

Can I use any battery that fits in the slot?

No. You must use the exact model number listed in your manual or printed on the old battery. Using the wrong battery can cause the watch to run fast or slow, drain quickly, or damage the circuit board. The cost difference between battery types is small, so always buy the correct one.

What if I lose a screw while opening the case back?

Most watch screws are standard sizes and can be replaced at a jewelry store or online for $1 to $5. Take the watch with you so the jeweler can match the size and thread. You can also order replacement screws online if you know the exact size, though this takes longer than buying one in person.

Is it safe to touch the battery with my fingers?

Touching the battery briefly won't ruin it, but oils from your skin can reduce its lifespan slightly. Use a plastic tweezers or wear clean gloves if you're concerned. Avoid touching the metal contacts on the battery or inside the watch, as this can cause corrosion.

Why did my watch stop working after I changed the battery?

The most common reason is that the battery is installed upside down — the positive (+) side must face outward. Open the case back and flip the battery. If it still doesn't work, try a new battery from a different package, as the first one may be defective. If a second battery doesn't work, your watch may need professional repair.