The fastest and cheapest places to replace a key fob battery

You can replace a key fob battery yourself at home for $3 to $8, or have someone else do it for $10 to $50 depending on where you go. A dealership charges the most — usually $50 to $100 — but will program a new fob if yours is damaged. A locksmith or big-box retailer like Best Buy or Walmart costs less and takes 10 to 15 minutes. If you want to do it yourself, most fobs open with a coin or flathead screwdriver, and the battery type is printed inside the case.

The choice depends on whether you want to spend time or money. If your fob works otherwise and you just need a new battery, a retailer or locksmith saves you $30 to $80 compared to a dealership. If the fob is cracked, won't hold a charge, or the buttons stick, a dealership is worth the cost because they can replace the whole unit and reprogram it to your car in one visit.

Key Takeaways

  • Most key fob batteries cost $3 to $8 and take five minutes to swap yourself if you have a coin or screwdriver.
  • Walmart, Best Buy, and independent locksmiths charge $10 to $50 to replace the battery and usually finish while you wait.
  • Dealerships charge $50 to $100 but will replace the entire fob and reprogram it if the battery replacement does not fix the problem.
  • The battery type is printed inside your fob case, so you can buy the right one before you go anywhere.

Doing it yourself at home

Opening most key fobs takes a coin or flathead screwdriver and two minutes. Look for a seam or slot on the edge of the fob — slide the coin into it and twist gently to pop the case open. Some fobs have a small button or lever on the back that releases the battery compartment instead. Once the case is open, note which side of the battery faces up, then lift it out with your fingernail or a plastic tool.

The battery type is stamped on the inside of the fob case or on the old battery itself — common types are CR2032, CR2025, and CR2016. Buy the matching battery at any pharmacy, grocery store, or dollar store for $3 to $8. Slide the new battery in with the same side facing up as the old one, close the case, and test the fob. If the buttons still do not work, the problem is not the battery — the fob may need professional repair or replacement.

The main risk is putting the battery in backwards or cracking the plastic case if you pry too hard. If the case cracks, the fob will still work but may stop responding to water or dust. If you are not comfortable opening it, a retailer or locksmith can do it for you for $10 to $30.

Walmart and other big-box retailers

Walmart, Best Buy, and Target all replace key fob batteries while you wait, usually in 10 to 15 minutes. You do not need an appointment. Walk into the store, go to the customer service desk or electronics section, and ask for battery replacement. Bring your fob and your car keys so they can test it before you leave. The cost is typically $10 to $20 plus the battery itself, which they usually have in stock.

Best Buy is often faster than Walmart because the Geek Squad counter is dedicated to small repairs. Walmart's service desk handles returns, complaints, and key fob batteries all in one line, so wait times vary. Target offers the service at some locations but not all — call ahead to confirm. None of these retailers will reprogram a fob if it stops responding after the battery is replaced, so if that happens you will need a locksmith or dealership.

Independent locksmiths

A local locksmith can replace your key fob battery for $15 to $40 and will often reprogram it if needed. Search "locksmith near me" or check Google Maps for locksmiths in your area, then call and ask if they do key fob batteries. Many will tell you the price over the phone. Some locksmiths will come to your car if you are stuck, though that costs more than visiting their shop.

Locksmiths are useful if your fob needs reprogramming or if you need a new fob cut and programmed to match your car. They can usually do this faster than a dealership and for less money. If a locksmith says they cannot help, ask them to recommend a dealership — they often work with the same ones and can tell you which one is fastest in your area.

Car dealerships

A dealership charges $50 to $100 to replace a key fob battery and will reprogram the fob if it stops working after the swap. They have the programming equipment on site and can test the fob against your car's security system. If your fob is cracked, the buttons are stuck, or it will not hold a charge even with a new battery, a dealership will replace the entire unit and program it in one visit — this usually costs $100 to $200 depending on your car's make and model.

Dealerships are the most expensive option but the right choice if the fob itself is damaged or if you need a new one. They can also order a replacement fob if they do not have your model in stock, though that adds a day or two to the timeline. Call ahead to ask if they have your fob in stock and what the total cost will be, including programming.

What battery type your fob uses

The battery type is printed on the inside of your fob case or on the battery itself. The most common types are CR2032 (used in most car fobs), CR2025, and CR2016. If you cannot find the type printed anywhere, search your car's year, make, and model plus "key fob battery" online — a parts website or forum will usually list it.

Once you know the type, you can buy the battery before you go to a retailer or locksmith, which saves time. Batteries are sold at pharmacies, grocery stores, dollar stores, and online. A single battery costs $3 to $8. If you buy a pack of two or four, the per-battery cost is usually lower. Check the expiration date on the package — batteries can sit in storage for years, but a fresh one is more reliable.

When to replace the whole fob instead of just the battery

If the fob is cracked, the buttons stick or do not respond, or the battery dies again within a few weeks, replacement is usually cheaper than repeated repairs. A new fob from a dealership costs $100 to $200 and includes programming. A new fob from a locksmith or online retailer costs $30 to $80, but you will need to pay a locksmith or dealership to program it — add another $50 to $100 to that cost.

If your fob is old and the battery replacement does not fix the problem, ask a locksmith or dealership whether a new fob or a repair makes more sense for your car. Some cars have fobs that are expensive to replace, so a repair is worth trying first. Others have cheap fobs, so replacement is the faster option.

Frequently Asked Questions

Can I replace the battery in my key fob myself?

Yes, most fobs open with a coin or flathead screwdriver and take five minutes. The battery type is printed inside the case. Buy the matching battery at a pharmacy or dollar store for $3 to $8, swap it in, and test the fob. If you are not comfortable opening it, a retailer or locksmith can do it for $10 to $30.

How long does a key fob battery last?

Most key fob batteries last three to four years with normal use. If you use the fob heavily — pressing the buttons many times per day — the battery may last only one to two years. A battery that dies within a few weeks of replacement usually means the fob itself is damaged and needs replacement, not just a new battery.

Will Walmart or Best Buy reprogram my key fob?

No, they replace the battery only. If the fob stops responding after the battery is replaced, you will need a locksmith or dealership to reprogram it. Call ahead and ask whether they offer reprogramming, because not all locations do.

What is the difference between a dealership and a locksmith for key fob work?

A dealership charges more but has your car's exact security codes on file and can reprogram a fob in minutes. A locksmith charges less but may need to reprogram the fob using a scanner, which takes longer. For a straightforward battery replacement, both cost about the same. For a new fob or reprogramming, a locksmith is usually cheaper.

Can I buy a key fob battery online and replace it myself?

Yes, you can order the battery online and replace it yourself. Search for your car's year, make, and model plus "key fob battery" to find the right type. Order from Amazon, eBay, or a pharmacy website. Delivery usually takes two to five days. Once it arrives, follow the steps above to open the fob and swap the battery.