Best Group 27 Marine Battery (2026): AGM, Flooded or Lithium?

Short answer: For trolling motors and house loads, the best Group 27 marine battery is the Pro-Guide Group 27 AGM Deep Cycle. It has 175 minutes of reserve capacity and 600 CCA, it's sealed and maintenance-free, and it weighs 50 lb. For engine starting, the Group 27 AGM Starting battery delivers 935 MCA. The best value is the 27M800 flooded dual purpose battery (800 CCA, 182 minutes), sold through dealers. To go lithium in a Group 27 space, the Group 24 24M100 (100Ah, 23.8 lb) fits with an adjustable box or a Group 24 tray.

Group 27 sits between Group 24 and Group 31. It is about 12 in long, which leaves room for more lead-acid capacity than a Group 24 without taking up as much space as a Group 31. Here is how the Pro-Guide Group 27 lineup compares.

Key Takeaways

• Best deep cycle: Group 27 AGM Deep Cycle, with 175 minutes of reserve capacity, sealed.
• Best starting: Group 27 AGM Starting, with 750 CCA and 935 MCA.
• Best value: 27M800 flooded dual purpose, with 800 CCA, 1,000 MCA and 182 minutes of reserve capacity, sold through dealers.
• All Pro-Guide Group 27 lead-acid batteries weigh 47 to 50 lb.
• Lithium option: a Group 24 lithium battery fits a Group 27 space and weighs less than half as much.

Best Group 27 Marine Batteries at a Glance

Best for	Battery	Key ratings	Weight	Warranty
Trolling and house loads	Group 27 AGM Deep Cycle	600 CCA, 175 min RC	50 lb	24-month free replacement
Engine starting	Group 27 AGM Starting	750 CCA, 935 MCA	50 lb	18-month free replacement
Best value, start + run (dealer)	27M800 flooded dual purpose	800 CCA, 1,000 MCA, 182 min RC	49 lb	12-month free replacement, 30-month pro-rata
Trolling on a budget (dealer)	27M180 flooded deep cycle	675 CCA, 180 min RC	50 lb	12-month free replacement, 30-month pro-rata
RV and light deep cycle (dealer)	27M160 deep cycle	600 CCA, 750 MCA	47 lb	12-month free replacement, 30-month pro-rata

CCA = cold cranking amps. MCA = marine cranking amps. RC = reserve capacity in minutes at 25 amps.

The Picks, Explained

Best deep cycle: Group 27 AGM Deep Cycle

With 175 minutes of reserve capacity, the Group 27 AGM Deep Cycle is our top Group 27 choice for trolling motors, electronics and house loads. AGM construction means no watering and no spills, and its 600 CCA can also start smaller engines. It comes with a 24-month free replacement warranty.

Best starting: Group 27 AGM Starting

The Group 27 AGM Starting battery delivers 750 CCA and 935 MCA in a sealed case. Choose it when you have a separate deep cycle battery for your accessories and want strong, maintenance-free cranking.

Best value: 27M800 flooded dual purpose (dealer)

The 27M800 has the most cranking power in our Group 27 lineup (800 CCA, 1,000 MCA) and 182 minutes of reserve capacity, so one battery can start the engine and run accessories. As a flooded battery, it needs periodic water checks.

Trolling on a budget: 27M180 flooded deep cycle (dealer)

The 27M180 gives 180 minutes of reserve capacity for trolling motors at the lowest up-front cost in the lineup.

RV and light deep cycle: 27M160 (dealer)

The 27M160 is the lightest Group 27 in the lineup at 47 lb, with 600 CCA. It suits RVs, campers and lighter deep cycle loads.

Pro-Guide flooded batteries are sold through dealers. Call 1-800-827-3232 to find one near you.

Going Lithium in a Group 27 Space

Pro-Guide doesn't make a lithium battery in a Group 27 case, but a Group 27 compartment can still go lithium. The 24M100 is a 12.8V, 100Ah Group 24 battery (10 1/4 x 6 13/16 x 9 3/16 in) that weighs 23.8 lb, less than half the weight of any Group 27 lead-acid battery we sell. It is about 1 13/16 in shorter than a Group 27, so secure it with a Group 24 tray or the adjustable Group 24-31 box. It is 9 3/16 in tall, slightly taller than our Group 27 batteries (8 1/5 to 8 7/8 in), so check your lid clearance.

The 24M100 is a deep cycle battery and is not designed for engine starting. If you need lithium cranking power in a smaller case, see the Group 24 lithium starting battery.

Group 27 vs. Group 24 and Group 31

Size	Length	AGM deep cycle reserve capacity	AGM deep cycle weight
Group 24	10 1/4 in	150 min	42 lb
Group 27	12 in	175 min	50 lb
Group 31	13 in	205 min	72.75 lb

If you have the space and want more runtime, a Group 31 adds 30 minutes of reserve capacity over a Group 27. See the best Group 31 marine battery guide and the battery group size chart.

Frequently Asked Questions

What is the best Group 27 AGM marine battery?

For deep cycle use, the Pro-Guide Group 27 AGM Deep Cycle, with 175 minutes of reserve capacity and 600 CCA. For starting, the Group 27 AGM Starting battery, with 750 CCA and 935 MCA.

Is a Group 27 battery good for a trolling motor?

Yes. A Group 27 deep cycle battery, such as the Group 27 AGM (175 minutes reserve capacity) or the 27M180 (180 minutes), is a common trolling motor choice. Use one for 12V, two in series for 24V or three in series for 36V.

How much does a Group 27 marine battery weigh?

Pro-Guide Group 27 lead-acid batteries weigh 47 to 50 lb.

Is there a lithium Group 27 battery?

Pro-Guide doesn't make one. The Group 24 24M100 (100Ah, 23.8 lb) fits a Group 27 space with a Group 24 tray or an adjustable Group 24-31 box.

Can a Group 27 battery start my boat and run electronics?

A dual purpose battery can. The 27M800 offers 800 CCA, 1,000 MCA and 182 minutes of reserve capacity. The Group 27 AGM Deep Cycle also has 600 CCA for smaller engines.

Shop Group 27 Batteries

Choose AGM for sealed, maintenance-free power, flooded for the lowest up-front cost, or move to a Group 24 lithium battery for the biggest weight savings.

SHOP THE GROUP 27 AGM DEEP CYCLE

Browse all AGM batteries, or call our team at 1-800-827-3232 for help or to find a dealer.

Built for the Water. Powered by Pro-Guide.