Yard Force 40V or 20V lawn mower: which battery fits?
Updated: October 2026
A Yard Force title can say 40 V while the battery is two 20 V packs. GR40 uses one 40 V battery. CR20 uses 20 V batteries. A 2×20 V mower uses two CR20 packs together. They are separate systems, so a pack you already own helps only if the family and the model match. Prices are on the [Yard Force lawn mower comparison](/hub/lawn-and-garden-equipment/yard-force-lawn-mower). This page says which battery belongs to each machine, and what a spare adds to the cost. Figures are the 15 October 2026 amazon.co.uk extracts. A purchase through our links can earn a commission at no extra cost to you.
A Yard Force title can say 40 V while the battery is two 20 V packs. GR40 uses one 40 V battery. CR20 uses 20 V batteries. A 2×20 V mower uses two CR20 packs together.
A Yard Force title can say 40 V while the battery is two 20 V packs. GR40 uses one 40 V battery. CR20 uses 20 V batteries. A 2×20 V mower uses two CR20 packs together. They are separate systems, so a pack you already own helps only if the family and the model match. Prices are on the Yard Force lawn mower comparison. This page says which battery belongs to each machine, and what a spare adds to the cost. Figures are the 15 October 2026 amazon.co.uk extracts. A purchase through our links can earn a commission at no extra cost to you.
Our top picks
| Badge | Product | Battery platform | Cutting width | In the box | Note | Price | Offer |
|---|---|---|---|---|---|---|---|
| Best overall |  Yard Force Yard Force LM G32 | 40 V 2.5 Ah and quick charger | 32 cm | Mower, battery, charger, manual | 8.2 | about £159.99 | View offer |
| Alternative |  Yard Force Yard Force LM C37B | CR20, two 4.0 Ah packs; charger in the title | 37 cm | Two 20 V batteries stated; charger stated in the title | 8.2 | about £199.99 | View offer |
| Preis-Tipp |  Yard Force Yard Force LM C33 | 20 V 4.0 Ah, charger stated | 33 cm | Mower, 20 V 4.0 Ah battery and charger (bullets) | 8.0 | about £118.50 | View offer |
On this page
GR40, CR20 and 2×20 V are not one battery shelf
Identify a Yard Force 40V or 20V lawn mower by battery family before the headline voltage. The LM G32, LM G34A and LM G37A use one 40 V GR40 pack. The LM G32 and LT G30 twin pack shares one 40 V battery between mower and trimmer. A GR40 label points at these machines, still subject to the exact model on Yard Force's compatibility list.
The LM C33 and the cylinder LM C38A run from one 20 V CR20 pack. The LM C33B and LT C25B set shares one CR20 battery between its two tools. The LM C37B is the naming trap: the title says 40 V, and the listing says two 20 V 4.0 Ah CR20 batteries. Yard Force places that model in the 2×20 V range, not on GR40.
A CR20 pack will not run a GR40 mower, and a GR40 pack is not a larger CR20. Check family, pack count and model as three separate facts. The buying guide puts platform before width and price if you are still choosing the machine.
Which mower in this comparison takes which pack?
The single-pack GR40 group is the LM G32, LM G34A and LM G37A, each listing a 2.5 Ah 40 V battery and charger, at 32 cm, 34 cm and 37 cm. The LM G32 and LT G30 bundle is the same family and lists one shared pack, not a second battery for the trimmer.
The single-pack CR20 group is the 33 cm LM C33 and the 38 cm LM C38A, both with a 4.0 Ah pack. The LM C33B and LT C25B bundle lists one 5.0 Ah CR20 battery for both tools. Use it with CR20 tools you already own only if that pack is approved for the model.
The LM C37B needs two 20 V 4.0 Ah CR20 batteries at once. One correct-family pack is not enough, and a flat pack in the pair stops the intended output. The EM U32 is neither family: a 1,200 W corded mower, supplied as a mower only. The narrow decks are compared in the small-garden guide.
What a spare battery costs against the mower
During research, Yard Force's UK battery shop listed a GR40 2.5 Ah pack at £79.99 and a CR20 20 V 2.5 Ah pack at £39.99. A separate 40 V page naming the LM G32 and LT G30 was £69.99. Those are snapshots, not today's price, and the two 40 V pages are not automatically the same product.
Against the extract, the LM G37A was £145.21, so a £79.99 GR40 spare is more than half the mower. The LM G32 was £159.99, so a £69.99 spare is still a large part of ownership. The LM C33 was £118.50. The £39.99 CR20 2.5 Ah price is a lower spare entry, and it is not a capacity match for a 4.0 Ah or 5.0 Ah pack in the box. The right connector does not prove Yard Force approves the combination. Match model and voltage before you order.
Common questions
Will a 20 V CR20 battery fit a GR40 mower?
No cross-compatibility is supported by the evidence used here. GR40 mowers use a single 40 V GR40 pack, while CR20 tools use one or two 20 V CR20 packs. Match the family and the exact mower model on the battery's compatibility list before you buy. A similar voltage printed in a title is not that match.
What does 40 V mean on the LM C37B?
For the LM C37B, 40 V describes the combined output of two 20 V CR20 batteries. It does not mean the mower takes one GR40 battery. The listing states two 20 V 4.0 Ah packs, and Yard Force includes this model in its 2×20 V range. One CR20 pack, even from the right family, is not enough to run it as specified.
Does the LM G32 use the same battery family as the LM G34A?
Both listings place the LM G32 and the LM G34A on the single-pack GR40 side, with a 40 V 2.5 Ah battery stated. You should still verify the exact battery product and the model compatibility before ordering a spare. Similar voltage labels are not enough on their own, and two 40 V shop pages are not automatically the same pack.
Can one battery run both a mower and a trimmer?
Yes. The two twin packs here are sold around one shared battery. You move it between the mower and the trimmer, so the tools cannot run at the same time. The charge left after mowing decides whether you can trim immediately, unless you already have a second compatible pack.
Is the EM U32 a CR20 mower?
No. The EM U32 is a 1,200 W corded mower with no battery, so neither CR20 nor GR40 applies. It needs a suitable outdoor mains arrangement and RCD protection rather than a Yard Force charger. The included-components line is the lawnmower only.
What should I read on the battery label?
Check the family name, nominal voltage, capacity in amp-hours, product code and compatibility wording. Compare those details with the mower's full model number and the required pack count. If the seller's title conflicts with the label or the manual, confirm with Yard Force support before you order.
Related pages
Sources
Sources checked for this comparison; amazon.co.uk prices, stars and review counts are the 15 October 2026 extracts.
- Yard Force UK GR40 lawnmowers (retrieved 15 October 2026)
- Yard Force UK CR20 range (retrieved 15 October 2026)
- Yard Force UK batteries and chargers (retrieved 15 October 2026)
- B&Q, Yard Force LM G34A (retrieved 15 October 2026)
- RHS, how to mow a lawn (retrieved 15 October 2026)
- Outdoor noise regulations, Schedule 3 (retrieved 15 October 2026)
- Electrical Safety First, lawnmowers (retrieved 15 October 2026)
- GOV.UK, battery and electrical waste recycling (retrieved 15 October 2026)
- amazon.co.uk listings for the ASINs in this comparison (retrieved 15 October 2026)