There isn’t a single battery size for every Subaru; the size depends on the model and year.
In most non-hybrid Subaru vehicles, the battery is a 12-volt lead-acid unit sized to fit the vehicle’s electrical demands. The exact "group size" (the standardized dimensions and terminal layout) varies by model and trim, with Group Size 35 being a common choice for many mainstream Subarus, while some older or specialty models use different sizes. Always verify using the vehicle’s manual, the current battery label, or Subaru’s parts catalog.
How to determine the exact battery size for your Subaru
To find the exact group size for your Subaru, use these steps:
- Check the owner's manual or the original documentation for the documented battery group size.
- Inspect the current battery's label or sticker on the top; look for "Group Size" or "BCI" followed by a code (for example, "Group Size 35").
- Use your vehicle identification number (VIN) to look up the recommended battery size in Subaru’s official parts catalog or a reputable auto parts retailer’s fitment tool.
- Tell the parts counter your car’s year, model, trim, and engine so they can confirm the correct size and type (flooded vs. AGM).
- Consider climate and driving habits; some Subaru models benefit from an AGM battery in colder climates due to higher resistance to parasitic drains.
Using these steps will help ensure you select a compatible battery size that fits physically and meets the car’s electrical needs.
Common sizes you may encounter in Subaru models
Note: exact sizes vary by year and trim; this is a general guide based on typical factory setups for mainstream Subarus in recent generations.
- Group Size 35: A widely used size for many mid-2000s to 2020s Subaru models (Outback, Legacy, Forester, Impreza, etc.).
- Group Size 24F or similar smaller/older formats: Found in some earlier models or specific trims; always verify your own vehicle.
- AGM variants: Several newer or high-demand configurations use an AGM (Absorbent Glass Mat) battery for better cold-cranking performance and longer life, especially in models with more electrical load or in colder climates.
The above lists are not exhaustive; there are exceptions by model line and market. Always confirm with a label or official catalog.
Battery type considerations
Most Subaru non-hybrid cars use standard flooded 12V batteries, though some later models and trims provide OEM AGM options. AGM batteries tolerate deeper cycling and reduce parasitic drain, which can be helpful in areas with extreme temperatures or if you use added electronic accessories. If you plan to upgrade, ensure the replacement fits the battery tray and has equivalent or better CCA and Ah ratings as specified by Subaru for your model.
Special note on hybrids and electric Subarus
Subaru's hybrid models (for example, older Crosstrek Hybrid) still rely on a separate 12V auxiliary battery in addition to the high-voltage traction battery. The “size” discussed here refers to that 12V auxiliary battery used for starting and electronics, not the HV pack. Always follow the service manual for high-voltage battery handling and replacement procedures.
Summary
There is no single, universal battery size for Subaru vehicles. The correct size depends on the specific model year and trim. Most non-hybrid Subarus use a 12V lead-acid battery with a common group size around 35, but exact size should be verified by checking the battery label, the owner's manual, or Subaru’s official parts catalog. When replacing, consider OEM recommendations, the climate, and whether an AGM battery is appropriate.