You can change most watch batteries yourself with three basic tools

A watch battery replacement takes about 10 minutes and costs $3 to $15 for the battery itself. You need a case opener (a flat tool that pries the back off), a small screwdriver that fits your watch's screws, and tweezers to handle the battery without touching it with your fingers. Most drugstores, jewelers, and online retailers sell watch battery kits with all three tools for under $10. If your watch is waterproof or has a sealed case, a jeweler should do this work instead—opening it yourself can break the seal.

The process is the same whether your watch is digital or analog: remove the case back, take out the old battery, note its size number, insert the new one the same way, and close the case. The hardest part is usually getting the case back off without scratching the watch. This guide walks you through each step so you do not damage the watch or the battery.

Key Takeaways

  • You need a case opener, small screwdriver, and tweezers—all available in a watch battery kit for under $10.
  • The battery size is printed on the old battery itself, so you know exactly what to buy as a replacement.
  • The positive side of the battery (marked with a + sign) must face up inside the watch case.
  • If your watch is waterproof or has a sealed back, take it to a jeweler instead of opening it yourself.
  • Avoid touching the new battery with bare fingers, because skin oils can shorten its life.

Gather your tools and the correct replacement battery

Before you open the watch, buy the right battery. The easiest way is to open the case back first, remove the old battery, and read the number printed on it—something like SR626, CR2032, or LR44. Write that number down and buy an identical replacement. If you cannot open the case back easily, take a photo of your watch and search online for "[watch brand] [model number] battery size" to find the part number before you start.

A watch battery kit from Amazon, Walmart, or a drugstore includes a case opener, a small screwdriver set, and tweezers for $8 to $12. If you already have a flat-head screwdriver and tweezers at home, you only need to buy the case opener separately (around $3 to $5). Do not use a kitchen knife or butter knife to pry the case open—you will scratch the watch and risk slipping and cutting yourself.

Open the case back without scratching the watch

Lay the watch face-down on a soft cloth or towel so the back is facing up. This protects the crystal (the clear front) from scratches. Look at the case back for a small notch or slot—this is where the case opener goes. If you see a small screw instead of a notch, use the screwdriver to remove it first, then use the case opener on the notch.

Insert the flat end of the case opener into the notch and explore steady, gentle pressure while you twist it slightly, as if you are opening a paint can. Do not force it—if it does not move after a few seconds of gentle pressure, the case back may be glued or sealed. Stop and take the watch to a jeweler instead. If the back begins to lift, slide the opener around the edge to break the seal all the way around, then lift the back off by hand.

Remove the old battery and note its orientation

Once the case back is off, you will see the battery sitting in a small metal holder or compartment. Use the tweezers to gently lift the battery straight up and out. Do not pry it sideways—you could damage the holder or the circuit board underneath.

Before you set the old battery down, look at which side was facing up. Most watch batteries have a + symbol on one side and a − symbol on the other. The + side should have been facing up toward the watch face. The new battery must go in the same way. If you forget which way it went, look at the metal holder—it usually has a small + or − mark stamped into it to show you the correct orientation.

Insert the new battery the same way the old one faced

Hold the new battery with tweezers and position it so the + side faces up (toward the watch face), matching the way the old battery sat. Gently lower it straight down into the holder until it sits flat. You should hear or feel a small click as it settles into place. If it does not click, lift it out and check that the + side is facing up, then try again.

Do not touch the battery with your bare fingers while you handle it. Skin oils can corrode the battery contacts and shorten how long the battery lasts. If you do touch it by accident, wipe it gently with a clean, dry cloth before you insert it.

Close the case back and test the watch

Align the case back with the watch body so the notch lines up with the opener slot. Press it down firmly until you hear a click—the back should sit flush with the case with no gap. If you removed a screw earlier, replace it now using the small screwdriver. Do not over-tighten the screw; stop as soon as you feel resistance.

Flip the watch over and check that it is running. If it is a digital watch, press a button to see the display light up. If it is analog, listen for a ticking sound or watch the second hand move. If nothing happens, the battery may be in backward. Open the case back again, flip the battery so the − side faces up, and close it. If the watch still does not work after that, the battery may be defective or the watch may need repair.

When to take your watch to a jeweler instead

Some watches should not be opened at home. If your watch is waterproof, has a sealed case back with no notch or screw, or is a luxury brand, take it to a jeweler. Opening a waterproof watch yourself breaks the seal, and water will damage the movement inside. A jeweler has the right tools to open and reseal it without breaking the waterproof rating.

If the case back will not budge after gentle pressure, or if you see glue around the edges, stop trying. Forcing it can crack the case or damage the internal parts. A jeweler can usually open it in a few minutes and will charge $10 to $25 for the service, plus the cost of the battery.

Frequently Asked Questions

How long does a watch battery usually last?

Most watch batteries last two to three years with normal use. Digital watches and watches with a backlight drain batteries faster and may need a replacement every one to two years. If your watch stops after only a few months, the battery may be defective or installed backward.

What if I put the battery in backward?

The watch straightforward will not work. Open the case back again, flip the battery so the + side faces up, and close it. There is no damage from installing it backward—the watch just will not run until you fix it.

Can I use any battery with the same number, or does the brand matter?

Any battery with the same part number (like SR626 or CR2032) will work. Brand does not matter much, though name-brand batteries from Energizer, Duracell, or Panasonic tend to last slightly longer than generic ones. The price difference is usually only $1 to $2.

Is it safe to throw the old battery in the trash?

Watch batteries are small and contain mercury or lithium, so check your local rules. Many communities have battery recycling programs at drugstores, electronics retailers, or hazardous waste facilities. Call your city or county waste management office to find a drop-off location near you.

Why does the jeweler charge so much if it only takes a few minutes?

Jewelers charge for the skill and tools, not just the time. They have specialized equipment to open sealed cases without damage and can fix problems if something goes wrong. If you damage the case or crystal trying to open it yourself, repair costs $50 to $200, so paying a jeweler $15 to $25 is often the safer choice.