A 377 silver-oxide battery is usually the best replacement for an SR626SW battery. Both have 1.55 V and are about 6.8 mm wide and 2.6 mm tall.

However, a battery that fits is not always the right replacement.

• 377 / SR66 / V377 / D377: normally compatible silver-oxide equivalents.
• 376 / SR626W: same size, but intended for higher-drain applications.
• AG4 / LR626 are alkaline batteries that might fit, but they use a different chemistry from silver-oxide batteries and do not perform the same way.

The safest approach is to buy a 377 or SR626SW silver-oxide battery if your old battery or device manual says SR626SW, unless the manufacturer recommends something else.

“SR” means the battery is silver-oxide. “SW” usually indicates a low-drain design for most analog quartz watches and other devices that need a steady voltage.

SR626SW Battery Equivalent Chart

Manufacturer cross-reference tables identify the 377, SR626SW, and SR66 family as 6.8 × 2.6 mm, 1.55 V silver-oxide watch cells. Murata’s watch battery selection guide and the Renata 377 datasheet are useful checks when a package uses unfamiliar branding.

For most watch replacements, yes. 377 is the most common code for SR626SW batteries in stores.

• Your old battery is marked SR626SW, SR626, SR66, or 377.
• The device manual specifies a 1.55 V silver-oxide battery.
• You are replacing a battery in a typical analog quartz watch.

1. Silver oxide chemistry
2. 1.55 V nominal voltage
3. A compatible code such as SR626SW, 377, SR66, V377, or D377

SR626SW and SR626W batteries are about the same size and use similar chemistry, but they are designed for different power needs.

If your watch has alarms, lights, or sensors, it might need a high-drain or multi-drain battery. Do not pick a 376 just because it is the same size. Check the old battery or the device manual first.

AG4 or LR626 batteries are about the same size, but they are usually alkaline 1.5 V batteries, not silver-oxide 1.55 V batteries.

This does not mean it will never work. In some cheap or low-drain devices, it might work for a short time. Still, it is not the best choice if your device needs an SR626SW battery, because alkaline and silver-oxide batteries last longer and perform differently.

• The old battery says SR, SW, 377, or SR626SW.
• The device is a watch or precision instrument.
• Stable voltage and predictable replacement intervals matter.
• You want to follow the manufacturer’s intended battery chemistry.

Only use an alkaline AG4 or LR626 if your device manual says it is okay or if the device came with that type of battery.

1. Read the old battery code.
   Check both sides of the removed cell. Look for SR626SW, 377, SR66, 376, LR626, or AG4.
2. Check the device manual or case-back marking.
   Always follow the device manufacturer’s instructions instead of general battery charts.
3. Match chemistry first.
   SR usually means silver oxide, and LR means alkaline. For SR626SW replacements, choose silver oxide if you can.
4. Match size and voltage.
   Make sure the replacement is about 6.8 mm by 2.6 mm and has a voltage of 1.55 V if it is silver-oxide.
5. Check drain type when relevant.
   Use SR626SW or 377 for most low-drain devices. Only use SR626W, 376, or a multi-drain battery if your device needs it.

1. Make sure your work area is clean, dry, and well-lit.
2. Open the battery compartment using the correct tool for the device.
3. Note the polarity before removing the old cell.
4. Try not to touch the new battery with your bare fingers. Use clean plastic tweezers or a non-metal tool if you can.
5. Put the new battery in with the same polarity as the old one, and make sure the clip holds it in place.
6. Test your device before you close the case all the way.
7. Recycle your used button battery at a proper collection point.

If your device is water-resistant, valuable, or hard to open, take it to a professional watch or electronics repair technician.

What battery is equivalent to SR626SW?

Is SR626SW the same as 377?

Can I use 376 instead of SR626SW?

Is AG4 the same as SR626SW?

Can LR626 replace SR626SW?

LR626 might fit because it is about the same size, but it is usually alkaline and 1.5 V. If your device needs SR626SW, use a 377 or SR626SW silver-oxide battery instead.