Subaru key fob batteries typically last three to four years and cost $3 to $15 to replace

Most Subaru key fobs use a coin-cell battery — usually a CR2032 or CR2025 — that you can replace yourself in under five minutes without tools or a trip to a dealer. The battery sits behind a removable cover on the fob's back or side. Once you pry open the case, slide out the old battery, note which side faces up, and insert the new one the same way. The entire process costs less than what a dealer charges for a single service visit.

If your fob stops locking or unlocking your doors, the battery is the first thing to check. A dying battery shows up as a weakening signal — you have to stand closer to your car, or press the button multiple times. Once it fails completely, the fob is dead until you replace it. Subaru does not sell fobs with pre-installed batteries, so you will need to do this step yourself or pay a dealer to do it.

Key Takeaways

  • Subaru key fobs use CR2032 or CR2025 coin-cell batteries that cost $3 to $15 and last three to four years on average.
  • You can replace the battery yourself by prying open the fob case, removing the old battery, and inserting a new one in the same orientation.
  • A weakening signal — needing to stand closer to your car or press multiple times — is the first sign the battery is dying.
  • Dealers will replace the battery for you, but the service call costs more than buying the battery yourself and doing it at home.

Finding the right battery for your Subaru fob

The battery type depends on your Subaru model year and fob design. Most recent Subaru fobs use a CR2032, which is the most common coin-cell battery sold in drugstores, supermarkets, and online retailers. Some older models use a CR2025, which is slightly thinner but the same diameter. Check your owner's manual or look inside the fob case itself — the battery type is printed on the old battery once you open it.

You can buy replacement batteries at any pharmacy, grocery store, or big-box retailer in the battery aisle. A single CR2032 costs between $3 and $8 depending on the brand and where you shop. Online retailers like Amazon sell multipacks of 10 or more for $5 to $15 total, which makes sense if you have multiple fobs or want spares on hand. Avoid buying the absolute cheapest option — a name-brand battery from Energizer, Duracell, or Panasonic will last longer and cost only slightly more.

Step-by-step battery replacement

Start by locating the seam on your fob. Most Subaru fobs have a small slot or groove on the back or side where the case splits in half. Use a coin, a flathead screwdriver, or your fingernail to gently pry the two halves apart. Do not force it — if it does not budge, try a different spot along the seam. Once the case cracks open, you will see the battery sitting in a small metal holder.

Note which side of the battery faces up — the positive side is usually marked with a plus sign and faces toward you. Gently pry or slide the old battery out of its holder. Drop in the new battery with the same side facing up. If you reverse the polarity, the fob will not work. Press the two halves of the case back together until you hear or feel a click. Test the fob by standing near your car and pressing the lock and unlock buttons.

If the fob still does not work after you replace the battery, the problem is not the battery. The circuit board inside may be damaged, or the buttons may be worn out. At that point, you have two options: buy a replacement fob from a dealer or a third-party seller, or have a dealer repair the existing one. A new OEM Subaru fob costs $150 to $300 depending on the model, while aftermarket fobs run $30 to $80.

When to replace the battery versus buying a new fob

Replace the battery if your fob is physically intact, the buttons respond when you press them, and the only problem is that it does not work from a distance or works intermittently. A fresh battery will restore full range and reliability. If the fob has visible cracks, the buttons are stuck or unresponsive, or water has gotten inside, a new battery will not fix it — you need a replacement fob.

Subaru dealers sell genuine OEM fobs that are programmed to your car during purchase. Third-party sellers on Amazon and eBay sell compatible fobs that are cheaper but may require you to program them yourself or pay a dealer to do it. Some newer Subaru models allow you to program a new fob using a sequence of button presses and ignition turns — check your owner's manual for the steps. If your model does not support self-programming, a dealer will charge $50 to $150 to program a new fob, whether it is OEM or aftermarket.

Dealer battery replacement service

Subaru dealerships will replace your key fob battery for you, but the cost is higher than doing it yourself. A dealer service call typically runs $50 to $100 in labor alone, plus the cost of the battery. Some dealers bundle it into a quick-service appointment or charge a flat diagnostic fee. If you are already at the dealer for another reason — a tire rotation, an oil change, or warranty work — you can ask them to replace the battery while you wait, which may save you a trip.

The advantage of dealer service is that they can diagnose whether the problem is actually the battery or something else inside the fob. If the fob is damaged and needs replacement, they can order a new one and program it on the spot. For most people, though, buying a $5 battery and spending five minutes at home is the faster and cheaper option.

Storing batteries and fob maintenance

Keep spare CR2032 batteries in a cool, dry place away from metal objects that could short the terminals. A plastic battery case or a small ziplock bag works well. Do not store batteries in a car where heat can degrade them, and do not leave them loose in a junk drawer where they might touch coins or keys.

To extend the life of your current fob battery, avoid leaving the fob in direct sunlight or in a hot car. Do not drop the fob or expose it to water — moisture can corrode the battery contacts and damage the circuit board. If your fob gets wet, remove the battery when ready, dry the inside with a soft cloth, and let it air-dry for a few hours before reinserting the battery. If water has already caused corrosion, a new battery will not help — you will need a replacement fob.

Frequently Asked Questions

Can I use any CR2032 battery, or does it have to be a Subaru brand?

Any CR2032 battery works in a Subaru fob. The battery itself is a standard part made by many manufacturers — Energizer, Duracell, Panasonic, and others all produce identical CR2032 cells. Buy from a reputable brand to may support quality and longevity, but you do not need a Subaru-branded battery.

What if I lose the fob case and cannot open it?

If the case is cracked or missing, you cannot safely replace the battery — water and dust will get inside and damage the circuit board. You will need to buy a replacement fob. Subaru dealers sell new cases and circuit boards separately if you want to salvage the electronics, but for most people, a new fob is simpler and cheaper.

How do I know if the battery is dead or if something else is wrong with the fob?

Try replacing the battery first — it is the cheapest and fastest test. If the fob works normally after you install a new battery, the problem was the battery. If it still does not work, the circuit board, buttons, or transmitter may be damaged, and you will need a replacement fob or dealer repair.

Can I program a new fob myself, or do I have to go to a dealer?

Some Subaru models allow self-programming using a sequence of ignition and button presses described in the owner's manual. Newer models may require dealer programming. Check your manual first — if self-programming is not listed, contact a dealer or a locksmith who works with Subaru fobs.