Quick answer
Almost every lawn mower battery is 12 volts, but the size depends on the mower. Riding mowers and zero-turns take a large Group U1 battery (our pick: UPLUS U1 360CCA AGM). Electric-start push mowers use small 3–4Ah packs, such as a YTX4L-BS on many Snapper mowers or a 12V 3.4Ah F1-terminal battery on Toro models. Match the size, terminals and polarity of your old battery, not just the voltage.
“12-volt mower battery” covers everything from a 3-inch starter pack under a push-mower handle to a 25-pound U1 tractor battery. Before you shop, read the label on your old battery, or measure it. Note the group (U1, YTX4L-BS…), the dimensions, the terminal type and which side the positive terminal is on.
| 1 |  | UPLUS U1 360CCA AGMBest for Riding Mowers | Check price |
| 2 |  | Mighty Max ML-U1-CCAHRBest Budget U1 | Check price |
| 3 |  | TYKOOL 20Ah U1 LithiumBest Lithium 12V | Check price |
| 4 |  | Mighty Max YTX4L-BS for SnapperBest for Electric-Start Push Mowers | Check price |
| 5 |  | ExpertPower YTX4L-BS 4AhBest High-Capacity Small Battery | Check price |
| 6 |  | Mighty Max ML3-12 for ToroBest for Toro Electric Start | Check price |
The best 12-volt lawn mower batteries
1UPLUS U1 360CCA AGMBest for Riding Mowers
A sealed AGM Group U1 battery rated 360 CCA and 26Ah. It’s maintenance-free and vibration-resistant, and is listed for John Deere, Cub Cadet, Husqvarna, Craftsman, Toro and other riders.
- Group: U1
- CCA / Ah: 360 / 26Ah
- Size: 7.68 × 4.92 × 6.93″
- Warranty: 15 months
Best For: Most lawn tractors and zero-turns.
Pros:
- Strong cranking
- Sealed AGM
- Wide fit
Cons:
- Check polarity
2Mighty Max ML-U1-CCAHRBest Budget U1
A 320 CCA sealed AGM U1 with nut-and-bolt terminals and the positive on the left. It’s also available as the U1R (positive on the right).
- Group: U1
- CCA: 320
- Size: 7.75 × 5.11 × 6.25″
- Polarity: positive left
Best For: Budget rider replacements.
Pros:
- Low price
- Both polarities offered
- Mounts in any position
Cons:
- No mounting hardware included
3TYKOOL 20Ah U1 LithiumBest Lithium 12V
A LiFePO4 U1 battery rated at 600A CCA, with a smart BMS, an LCD state-of-charge display and 3,000+ cycle life. It’s far lighter than lead-acid.
- Group: U1
- CCA / Ah: 600 / 20Ah
- Chemistry: LiFePO4 with BMS
Best For: A long-life, lightweight rider upgrade.
Pros:
- Very light
- Charge display
- Long cycle life
Cons:
- Higher price
- Confirm your charging system suits lithium
4Mighty Max YTX4L-BS for SnapperBest for Electric-Start Push Mowers
A 12V 3Ah, 50 CCA sealed AGM battery in the YTX4L-BS size used on many Snapper walk-behinds. It measures 4.40 × 2.90 × 3.42″ with the negative terminal on the left. It has a 1-year warranty.
- Size: YTX4L-BS (4.40 × 2.90 × 3.42″)
- Capacity / CCA: 3Ah / 50
- Polarity: negative left, positive right
Best For: Snapper and similar electric-start walk-behinds.
Pros:
- Cheap
- Sealed and spill-proof
- Direct size match
Cons:
- Wiring harness not included
5ExpertPower YTX4L-BS 4AhBest High-Capacity Small Battery
The same YTX4L-BS size with more capacity (4Ah) and a 120 CCA rating, for quicker cranking. It’s a sealed AGM battery that also replaces YT4L, GTX4L and GT4L.
- Size: YTX4L-BS (4.45 × 2.76 × 3.39″)
- Capacity / CCA: 4Ah / 120
- Type: sealed AGM
Best For: Push mowers that crank slowly on a 3Ah pack.
Pros:
- More capacity
- Higher CCA
- Same footprint
Cons:
- Confirm the terminal layout matches
6Mighty Max ML3-12 for ToroBest for Toro Electric Start
A 12V 3Ah sealed lead-acid battery with F1 terminals, listed as a replacement for Toro part 106-8397. It measures 5.28 × 2.64 × 2.64″ and has a 1-year warranty.
- Replaces: Toro 106-8397
- Capacity: 3Ah
- Terminals: F1
- Size: 5.28 × 2.64 × 2.64″
Best For: Toro electric-start walk-behinds that use this pack.
Pros:
- Low price
- UL certified
- Toro part match
Cons:
- Check your Toro’s part number
12-volt mower battery size guide
Riders and zero-turns
Group U1 (about 7.7 × 5 × 6.5–7″), 200–360+ CCA. Check whether the positive is on the left or the right (U1R).
Electric-start push mowers
Small 2.3–4Ah packs (YTX4L-BS, F1-terminal SLA). Match the brand part number.
Briggs InStart / lithium start
Proprietary removable packs, such as Briggs 597189. Buy the exact model.
Battery mowers
These use 40V–82V tool batteries, not 12V starter batteries.
Frequently asked questions
Are all lawn mower batteries 12 volts?
Starter batteries on gas mowers almost always are. A few vintage tractors used 6V, and battery-powered mowers use 40V–82V packs.
Can I use a motorcycle battery in my mower?
Yes, if the size, terminals, polarity and capacity match. Many small push-mower batteries share powersports sizes like YTX4L-BS.
How do I keep a 12V mower battery healthy?
Keep it charged, especially over winter. A smart maintainer is the easiest way. Keep the terminals clean, and recharge after short mowing sessions.
Related: Best lawn mower batteries · Trickle chargers for riding mowers · Lithium mower batteries
How we chose: This is a researched guide. We compared battery size, capacity, CCA, terminals, polarity and listed fitment from current product listings. We didn’t field-test these batteries.
Update log: November 2026: rebuilt the guide. We reorganized it by mower type (riders, push mowers, lithium), removed oversized deep-cycle batteries, and added a size guide and an FAQ.