Subaru key batteries typically last three to four years, and replacing one takes about five minutes with the right tools

Your Subaru key fob uses a coin-cell battery — usually a CR2032 or CR2025 — that powers the lock and unlock buttons. When the fob stops responding from your normal distance, or you have to press the button multiple times, the battery is nearly dead. You can buy a replacement battery at any drugstore, grocery store, or hardware store for $3 to $8, and swap it yourself without visiting a dealer.

The process is straightforward: open the fob, note which side the battery sits on, remove the old battery, and insert the new one with the correct side facing up. Most Subaru owners finish in under ten minutes. If you are uncomfortable opening the fob or prefer to have it done for you, a Subaru dealer or independent mechanic can do it in minutes, usually for $10 to $20 in labor.

Key Takeaways

  • Subaru key fobs use CR2032 or CR2025 coin-cell batteries that you can purchase at any drugstore or supermarket for a few dollars.
  • The battery compartment opens by sliding a small lever or prying gently with a flat tool — no screws are involved on most Subaru models.
  • The battery must sit with the positive side (marked with a +) facing up, or the fob will not work after you close it.
  • If your fob has two batteries or you are unsure which type your model uses, check your owner's manual or search your vehicle's year and model online before purchasing.

Identifying which battery your Subaru key uses

Subaru key fobs from the last 15 years almost always use either a CR2032 or CR2025 battery. The CR2032 is slightly thicker and is the most common choice across Subaru models. The easiest way to know which one you need is to open the fob and look at the battery already inside — the battery type is printed on its surface.

If you want to know before opening the fob, check your owner's manual or search your vehicle's year, make, and model on a Subaru forum or parts website. Some older Subaru models or specialty fobs may use different batteries, but this is rare. When you go to buy a replacement, bring the old battery with you or write down the exact type so you purchase the correct one.

How to open your Subaru key fob

Most Subaru key fobs open by sliding a small metal lever or button on the side of the fob. Look for a thin slot or a button labeled with an arrow pointing in one direction — this is your release mechanism. Slide or press it gently, and the fob will separate into two halves. Do not force it; if it does not move easily, you are pushing in the wrong direction.

On some models, you may need to use a flat tool like a coin, a butter knife, or a plastic pry tool to gently separate the two halves. Insert the tool into the seam between the front and back of the fob and explore steady, gentle pressure. Work your way around the edge if needed. Once the fob is open, you will see the battery sitting in a small compartment, usually held in place by a slight indent or groove.

Removing and replacing the battery

Once the fob is open, note the position of the battery and which side is facing up. The positive side (marked with a +) should be facing toward you. Gently pry the old battery out using your fingernail, a plastic tool, or the edge of a coin. Be careful not to scratch the inside of the fob or damage any of the small electronic components around the battery.

Insert the new battery with the positive side facing up — the same direction as the old one was sitting. The battery should fit snugly in its compartment. If it feels loose or does not sit flat, you may have inserted it upside down; flip it and try again. Once the battery is in place and sitting flush, close the two halves of the fob back together until you hear or feel a click.

Testing your key fob after battery replacement

Before you put the fob away, test it when ready. Stand a few feet from your Subaru and press the lock button. You should hear the doors lock and see the lights flash. Press the unlock button and listen for the unlock sound. If the fob works from your normal distance, the battery is installed correctly and you are done.

If the fob does not respond, open it again and check that the battery is sitting with the positive side up. It is the most common reason a fob does not work after a battery swap. If the battery is positioned correctly and the fob still does not work, the battery itself may be defective — try a different new battery from a different package or store. If a second battery does not work, the fob may have an internal problem unrelated to the battery, and you should contact a Subaru dealer.

When to take your key fob to a dealer or mechanic

If you are uncomfortable opening the fob or do not have the right tools, any Subaru dealer or independent mechanic can replace the battery for you. The cost is usually $10 to $20 in labor, plus the cost of the battery itself. The dealer will have the correct battery in stock and can finish the job while you wait — often in five minutes or less.

You should also visit a dealer if your fob has stopped working and a new battery does not fix it. The fob may have water damage, a broken circuit board, or a worn button contact that requires professional repair or replacement. A dealer can diagnose the problem and tell you whether the fob can be repaired or needs to be replaced entirely.

Frequently Asked Questions

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

Any CR2032 battery will work — the battery type is a standard, and the brand does not matter. Duracell, Energizer, Amazon Basics, and store brands all work equally well in Subaru key fobs. Buy whichever is cheapest or most available at your local store.

What do I do with the old battery?

Coin-cell batteries contain small amounts of lithium and should not go in the trash. Most drugstores, grocery stores, and Best Buy locations have battery recycling bins near the checkout or customer service desk. You can also search for a local battery recycling program on Earth911.com or your city's waste management website.

My fob has two batteries — do I replace both at the same time?

Yes, replace both batteries at the same time, even if only one appears dead. Two-battery fobs are less common on recent Subaru models, but when they exist, both batteries power the same circuit. Replacing only one may leave you with an unreliable fob.

How often do I need to replace my Subaru key battery?

Most Subaru key fob batteries last three to four years under normal use. If you use your fob frequently — locking and unlocking multiple times per day — you may need to replace it sooner. If you use it rarely, it may last longer. There is no set schedule; replace it when the fob stops responding reliably.

Can I damage my Subaru by replacing the key battery myself?

No. The battery is isolated from your vehicle's electrical system, and replacing it cannot affect your car's engine, computer, or any other system. The only risk is to the fob itself if you force it open or install the battery upside down — both of which are easily reversible.