How many years should a Subaru battery last?

Typically, a Subaru’s 12-volt starting battery lasts about 3–5 years. With high‑quality AGM batteries and favorable conditions, it can reach around 6–7 years, while very hot climates often shorten life to around 2–4 years. This answer covers what to expect, factors that affect lifespan, and tips to extend it.

What to expect from a Subaru 12-volt battery

The 12‑volt battery in most Subaru models powers engine starting, lighting, and accessories. In many vehicles it is a standard flooded lead‑acid battery, but some newer Subarus with advanced electrical loads or start‑stop systems may use an absorbed glass mat (AGM) battery. Lifespan depends on climate, driving patterns, maintenance, and the health of the charging system.

Battery types used by Subaru

Subaru’s older designs commonly used conventional flooded lead‑acid batteries. In recent years, certain trims or models with higher electrical demands may employ AGM batteries, which typically offer longer life and better performance in extreme temperatures, at a higher upfront cost.

Typical lifespans by conditions

These ranges reflect common experience for the 12‑volt battery across Subaru models, assuming regular use and typical maintenance. Individual results vary with battery type, charging system condition, and storage practices.

• Average climate with regular driving: about 3–5 years.


• Cooler climates with moderate parasitic drain: often 4–6 years.


• Hot climates or frequent short trips: commonly 2–4 years.


• High‑quality AGM battery with proper care: up to 6–7 years in favorable conditions.

Note: These are general ranges. Real-world lifespans can be shorter or longer based on model year, battery type, alternator health, and how the vehicle is used and stored.

How to maximize your Subaru battery life

Proactive maintenance and mindful usage can push the battery toward the upper end of its expected life.

• Keep terminals clean and tight; remove corrosion with a baking soda solution and a wire brush as needed.


• Have the charging system (alternator and voltage regulator) tested if you notice slow cranking or dim lights.


• Avoid excessive short trips; combine errands or use a battery tender if the car sits idle for long periods.


• Consider a battery maintainer or trickle charger during extended storage or seasonal use.


• Replace aging cables or clamps showing corrosion, and check for parasitic electrical drains.


• Use the correct battery type for your model (flooded vs. AGM) and follow Subaru’s recommendations for replacement.

Applying these practices helps you maximize the usable life of the battery and reduce the risk of unexpected failures.

Signs your Subaru battery may need replacement

Watch for indications that the battery is nearing the end of its life or that the charging system may be failing.

• Slow engine start or lengthy cranking before the engine fires up.


• Dim or flickering headlights, especially when the engine is idling.


• Dashboard battery warning light illuminated.


• Corrosion on terminals, a swollen battery case, or leakage.


• Voltage readings consistently below about 12.4V with the engine off, or inconsistent performance.

If you notice these signs, have the battery and charging system tested promptly to determine whether a replacement is needed.

Understanding replacement options

Subaru owners can choose between standard flooded lead‑acid batteries and high‑quality AGM batteries, depending on model year and equipment. AGM batteries offer longer life and better cold‑cranking performance in extreme temperatures but come at a higher upfront cost. Proper installation and adhering to model‑specific guidelines help ensure reliability.

Summary

For most Subaru models, the 12‑volt starting battery should last roughly 3–5 years in typical conditions. With high‑quality AGM batteries and favorable circumstances, you might reach 6–7 years, while hot climates and frequent short trips can shorten life to about 2–4 years. Regular maintenance, proper charging system health, and using the recommended battery type are the best strategies to maximize longevity. If you observe slow starts, dim lights, or warning indicators, have the system checked to plan a timely replacement.

Bottom line

Expect a practical lifespan of several years with variations based on climate, driving patterns, and battery technology. Staying ahead with maintenance and monitoring can prevent surprises and keep Subaru starting reliability strong for years to come.

How long should a factory Subaru battery last?

Subaru OEM batteries typically last 3 to 5 years, though this can vary based on usage and environmental factors. While some may last longer, it's best to have your battery checked after three years, as its efficiency will decline over time. 
Factors that influence lifespan

• Usage: Frequent short trips and heavy use of electronics can shorten the battery's life. 
• Environment: Extreme temperatures, especially heat and cold, can accelerate battery wear. 
• Maintenance: Proper maintenance, including cleaning the terminals, can help prolong the battery's life. 

Signs of a dying battery
Slow engine start, Dimming headlights and interior lights, Slow or non-functioning electrical components, Corroded or warped battery case, and A "rotten egg" smell coming from the battery.

How much does a new Subaru battery cost?

A Subaru battery replacement typically costs between $150 and $400, but can be higher or lower depending on the car's model, the type of battery, and where you get it serviced. You can expect to pay anywhere from $100-$250 for the battery itself and $50-$150 for labor, though some dealerships may charge upwards of $500 or more.
 
Cost breakdown

• Parts (battery): Expect to pay between $100$ 100$100 and $250$ 250$250 for a standard replacement battery. Some premium batteries can be more expensive, while OEM batteries are often slightly pricier but may offer a longer warranty. 
• Labor: The cost of labor can range from $50$ 50$50 to $150$ 150$150, depending on the shop and the complexity of the job. 
• Total cost: This results in an average total cost of around $150$ 150$150 to $400$ 400$400 for a full replacement. 

Factors that influence the cost

• Vehicle make and model: The specific Subaru model and year will influence the battery type and price. 
• Battery type: Standard lead-acid batteries are generally cheaper than AGM or other premium batteries. 
• Warranty: Some Subaru batteries have an initial three-year or 36,000-mile warranty. If you have a newer car and the battery is still under warranty, you may be able to get a free replacement. 
• Shop type: Prices can vary significantly between dealerships, auto parts stores, and independent repair shops. 
• Additional parts: In some cases, you may need to replace other components like the battery terminals, which can increase the total cost. 

How to get the best price

• Shop around: Compare prices at different places like auto parts stores (e.g., AutoZone, Advance Auto Parts) or independent mechanics before committing to a dealership. 
• Consider DIY: If you are comfortable with the process, you can save money by purchasing the battery yourself and installing it yourself. 
• Check for promotions: Keep an eye out for deals or coupons from auto parts stores or repair shops. 
• Ask about free battery tests: Many auto parts stores offer free battery testing to see how much life is left in your current battery before you replace it. 

Is $300 too much for a car battery?

Overall you can expect to pay somewhere between $100 and $300 on average for a brand-new battery to last you a few years.

When should a Subaru battery be replaced?

If it's approaching or past the five-year mark, it's wise to consider a replacement, even if it's still functioning. 4. Electrical Issues: A failing battery can manifest in various electrical problems within your Subaru.