The fastest places to buy a key fob battery
You can buy a key fob battery at any drugstore, supermarket, hardware store, or big-box retailer—they stock them in the checkout aisle or the battery section. Target, Walmart, CVS, Walgreens, and Rite Aid all carry the common sizes (CR2032, CR2025, and CR2016 are the most frequent). A single battery costs between $3 and $8 depending on the brand and where you shop.
If you need the battery today, a local pharmacy or grocery store is faster than waiting for shipping. If you already know your fob's battery size, you can call ahead to confirm they have it in stock. Many stores will also install it for free or for a small fee if you ask at the customer service desk—this takes five minutes and saves you the frustration of opening the fob yourself.
Key Takeaways
- Drugstores, supermarkets, and hardware stores stock key fob batteries in their battery aisles or near checkout, usually for $3 to $8 per battery.
- The most common sizes are CR2032, CR2025, and CR2016—check your fob's manual or the old battery itself to find out which one you need.
- Many retailers will install the battery for free if you ask, which takes about five minutes and eliminates the risk of damaging your fob.
- Online retailers like Amazon ship batteries cheaply but take one to three days, so use them only if you are not in a hurry.
- Car dealerships sell batteries at a markup but can program a new fob if your current one is damaged beyond repair.
How to find the right battery size before you shop
Open your fob and look at the battery itself—the size is printed on the top. Write down the number (it will be something like CR2032) and bring it with you to the store, or search for it online before you leave home. If you cannot open the fob without breaking it, check your car's owner manual; the manual usually lists the battery type in the key fob section.
If you have lost the manual, search online for "[your car make and year] key fob battery" and you will find the size within seconds. Do not guess—buying the wrong size wastes money and time. The battery must fit snugly in the compartment, or the fob will not work.
Drugstores and supermarkets
CVS, Walgreens, Rite Aid, and most grocery stores keep batteries in the health and beauty aisle or near the checkout counter. These stores are convenient if you are already shopping, and staff can usually install the battery on the spot. Call ahead if you want to confirm they have your specific size in stock.
Prices at drugstores are slightly higher than at big-box retailers, but the convenience often makes up for it. Many pharmacies will not charge you to install the battery if you buy it from them.
Hardware stores and big-box retailers
Home Depot, Lowe's, Ace Hardware, Walmart, and Target all stock batteries in their hardware or electronics sections. These stores usually have a wider selection of sizes and brands than drugstores, and prices are often lower. Walmart and Target batteries are typically the cheapest option if you are buying just one.
Staff at these stores can usually install the battery, though policies vary by location. Ask at the customer service desk or the electronics counter. Installation is usually free, but call ahead to confirm.
Online retailers and car dealerships
Amazon, eBay, and other online retailers sell key fob batteries in bulk packs—often 5 or 10 batteries for $5 to $10. This is the cheapest per-battery option if you buy in bulk, but shipping takes one to three days. Use this route only if you can wait or if you want to stock up for future use.
Car dealerships sell batteries at a significant markup (often $15 to $25 per battery) but can program a new fob if yours is physically damaged or no longer responds to a new battery. If your fob is cracked, waterlogged, or the buttons are stuck, a dealership is your only option—a new battery will not fix those problems.
How to install the battery yourself
Most key fobs open by sliding a small metal lever or prying gently with a flathead screwdriver along the seam. Look for a slot or notch on the edge of the fob—that is where you insert the lever. Slide it slowly; the two halves should separate without force. If you have to pull hard, you are likely prying in the wrong spot.
Once the fob is open, note which side of the battery faces up (usually the positive side, marked with a plus sign, faces toward you). Remove the old battery and slide the new one in the same way. Close the fob by pressing the halves together until they click. Test the buttons when ready to confirm it works.
Common mistakes: forcing the fob open and cracking the plastic, inserting the battery upside down, or not closing the fob completely so the battery loses contact. If the fob still does not work after you install a new battery, the problem is likely the circuit board or buttons, not the battery—take it to a dealership.
Comparing your options
| Where to Buy | Price Per Battery | Speed | Installation Available |
|---|---|---|---|
| Drugstore (CVS, Walgreens) | $5–$8 | Same day | Usually yes, free |
| Supermarket | $4–$7 | Same day | Sometimes |
| Hardware store (Home Depot, Ace) | $3–$6 | Same day | Usually yes, free |
| Big-box retailer (Walmart, Target) | $3–$5 | Same day | Sometimes |
| Online (Amazon, eBay) | $1–$2 (bulk packs) | 1–3 days | No |
| Car dealership | $15–$25 | Same day | Yes, included |
Frequently Asked Questions
Can I use any CR2032 battery or does it have to be a specific brand?
Any CR2032 will work in your fob—the size and voltage are standardized. Brand does not matter. Duracell, Energizer, and store brands all perform the same. Buy whichever is cheapest.
What if I open my fob and the battery compartment looks different than I expected?
Some fobs have a metal clip or spring that holds the battery in place. Make sure you do not lose this clip when you remove the old battery. Slide the new battery under the clip the same way the old one sat, then close the fob. If the clip is bent or missing, the battery will not make contact and the fob will not work.
How long does a key fob battery usually last?
Most key fob batteries last three to four years with normal use. If you use your fob multiple times a day, it may last only two years. If you rarely use it, it may last five years or longer. There is no way to predict exactly when it will die.
Should I replace the battery if my fob is getting old?
Only replace the battery if the fob stops working or the buttons become sluggish. Replacing a battery that still works wastes money. If you replace the battery and the fob still does not work, the problem is the circuit board or buttons, and a new battery will not fix it.
Can I buy a battery at a car dealership without an appointment?
Most dealerships will sell you a battery and install it while you wait, but call ahead to confirm. Some dealerships require an appointment or only do this during service hours. Expect to pay more than you would at a drugstore or hardware store.