You can replace most Fossil watch batteries yourself with a coin and a steady hand

A Fossil watch battery typically lasts two to three years before it stops powering the watch. When your Fossil stops keeping time, the battery is usually the culprit. You can replace it yourself without tools beyond a coin, a small flathead screwdriver, and a replacement battery that costs $3 to $8. The whole job takes about 15 minutes if you work carefully and keep track of the small parts.

The process is the same for most Fossil analog watches: pop off the case back, remove the old battery, drop in the new one, and seal it shut. The hardest part is not losing the tiny gasket—a rubber ring that keeps water out—when you open the case. This guide walks you through each step and shows you what to watch for so you do not damage the watch or the seal.

Key Takeaways

  • Fossil watch batteries are standard sizes (usually SR626SW, SR927SW, or SR920SW) that you can buy at drugstores, supermarkets, or online for a few dollars.
  • The case back is held on by a small notch or groove, not screws, and you open it by inserting a coin into the slot and twisting gently counterclockwise.
  • The gasket is a thin rubber ring around the inside edge of the case back—do not lose it, and do not force it, or water will leak into the watch.
  • Once you remove the old battery, note which side faces up before you drop in the new one, because batteries only work one direction.
  • If the watch still does not work after you install a fresh battery, the movement may be damaged and you will need a professional repair.

Find out what battery size your Fossil watch uses

Before you open the watch, you need to know which battery to buy. The easiest way is to check the Fossil website or your watch manual—search for your watch model number and "battery size." The model number is usually printed on the case back or inside the band.

If you cannot find the manual, open the case back (follow the steps below) and look at the old battery itself. The battery will have a code stamped on it, like SR626SW or SR927SW. Write that code down and buy an exact replacement. Do not guess at the size—a battery that is too thick will not fit, and one that is too thin will not make contact with the terminals.

You can buy Fossil watch batteries at CVS, Walgreens, Target, Walmart, or online at Amazon. Some jewelry stores and watch repair shops sell them too, though they may charge more. Make sure you buy a fresh battery—check the expiration date on the package, which is usually printed on the back.

Gather your tools and set up a clean workspace

You need very little to do this job. Gather a coin (a dime or penny works), a small flathead screwdriver, your new battery, and a small bowl or cup. The bowl is for holding the gasket and any tiny screws so you do not lose them on the floor.

Work on a clean, flat surface with good light—a kitchen table or desk is ideal. Avoid carpet, because if you drop the gasket or battery, it will disappear into the fibers. Wash your hands before you start so you do not transfer oils or dirt to the battery terminals, which can prevent the battery from making good contact.

Open the case back by twisting the coin slot counterclockwise

Look at the back of your Fossil watch. You will see a small notch or groove cut into the metal case back, usually near the edge. This is where you insert the coin. The groove is designed so a coin can grip it without slipping.

Insert a coin (dime or penny) into the groove so the edge of the coin sits in the notch. Push down gently and twist the coin counterclockwise—the same direction you turn to loosen a jar lid. You should feel slight resistance, but do not force it. If it does not budge after a gentle twist, try a different coin or check that you are turning the right direction. After one or two full rotations, the case back will come loose enough to lift off by hand.

Once the case back is loose, set the coin down and use your fingernail or the flathead screwdriver to pry the edge of the case back up gently. Lift it straight off and set it face-down on your clean surface. Do not flip it over yet—the gasket is sitting inside the rim, and you want to keep it in place.

Remove the gasket and the old battery without forcing anything

Look inside the case back. You will see a thin rubber ring (the gasket) pressed into a groove around the inside edge. This ring is what keeps water out of your watch. Do not pry at it or pull hard—if you damage it, the watch will no longer be water-resistant.

Gently lift the gasket out of its groove using your fingernail or the tip of the flathead screwdriver. Place it in your small bowl so it stays clean and you do not lose it. If the gasket is stuck, try breathing warm air on it for a few seconds to soften the rubber slightly, then try again.

Now look at the watch movement (the metal plate inside the case). You will see the battery sitting on top of it, usually held in place by a metal clip or spring. The battery is a small silver disc. Note which side is facing up—the positive side is usually marked with a + symbol. Gently lift the clip or spring and slide the old battery out. If there is no clip, just lift the battery straight up. Place the old battery in your bowl.

Insert the new battery and reseal the case back

Take your new battery and hold it so the positive side (marked with +) faces up, the same direction the old battery was facing. Slide it under the metal clip or into the same spot where the old battery sat. Make sure it sits flat and makes contact with the metal terminals on both sides. If the battery is loose or tilted, it will not work.

Now you need to put the gasket back. This is the step where most people make mistakes. Pick up the gasket from your bowl and inspect it for dirt or damage. If it looks clean, gently press it back into the groove around the inside edge of the case back. It should sit snugly all the way around. If there are any gaps or wrinkles, lift it out and try again. A gasket that is not seated properly will let water into the watch.

Once the gasket is in place, line up the case back with the watch body and press it down firmly. You should hear or feel a small click as it seats. Now insert your coin into the groove and twist clockwise (the opposite direction from when you opened it) until the case back is snug. Do not over-tighten—you are just sealing it, not clamping it. One or two firm twists is enough.

Test the watch and troubleshoot if it does not work

Once the case back is sealed, hold the watch to your ear. You should hear a faint ticking sound. If you do, the battery is working. Check that the hands are moving by looking at the second hand—it should sweep around the dial. If the watch is running, you are done.

If you do not hear ticking or see the hands moving, the battery may not be making contact. Open the case back again (following the same steps) and check that the battery is sitting flat and that both terminals are touching the metal contacts on the movement. Make sure the positive side is facing up. If the battery is positioned correctly and the watch still does not work, the movement itself may be damaged, and you will need to take the watch to a professional repair shop.

If the watch works but stops after a few hours, the battery may be defective. Try a different new battery from a different package. If a second battery also fails, the movement is likely the problem.

Frequently Asked Questions

Can I replace a Fossil watch battery if the case back is glued on?

Some Fossil watches, especially older models or those with special finishes, have case backs that are glued rather than screwed. If you cannot open the case back with a coin after gentle twisting, it is probably glued. Do not force it—you will crack the case. Take it to a watch repair shop or a Fossil store, where they have the right tools to open it without damage.

What if I lose the gasket or it tears when I remove it?

A damaged or missing gasket means the watch is no longer water-resistant. You can still wear it, but do not expose it to water or humidity. Replacement gaskets are inexpensive (usually $2 to $5) and are available from watch repair shops or online. A repair shop can install a new gasket for you if you do not want to open the case again.

How do I know if I bought the wrong battery size?

If the battery does not fit into the space where the old one sat, or if it is so loose that it rattles, you have the wrong size. Do not force it in. Take it back to the store and exchange it for the correct size. Always check the code on the old battery before you buy a replacement.

Is it safe to replace the battery myself, or should I go to a jeweler?

Replacing a Fossil watch battery yourself is safe if you work slowly and do not force any parts. The main risk is damaging the gasket, which costs a few dollars to replace. If you are uncomfortable opening the case or worried about the gasket, a jeweler or watch repair shop will do it for $10 to $25, which is still cheaper than buying a new watch.

Why did my watch battery die so quickly?

Fossil watch batteries typically last two to three years with normal wear. If yours died in a few months, the watch may have a problem that is draining the battery faster than normal—a short circuit in the movement, for example. If a new battery also dies quickly, take the watch to a repair shop to have the movement checked.