Specs from the makers' own documentation Battery compatibility built in UK retailer prices, updated daily 25+ years of trade experience
‹ All Milwaukee M12 batteries
M12 Milwaukee M12B3
Fits
35 Milwaukee M12 toolsSee them ›
Charges
50 min on 2 of the 5 chargers Milwaukee lists for itCharge times ›
Specs
From Milwaukee's own documentationChecked 27 Sep 2026
Milwaukee · M12 platform

Milwaukee M12B3 12V 3.0Ah REDLITHIUM battery

3.0Ah 36Wh 0.2kg Fuel gauge

Milwaukee M12 B3 3Ah 12V REDLITHIUM pack.

Adds it to My Tools, kept on this device
Lowest price we track
£29.95at Tooled Up · + £6.95 delivery
View at Tooled Up ›
Compare retailersTotal with delivery
Tooled Up Lowest£29.95 + £6.95 delivery£36.90View ›
My Tool Shed£29.95 + £6.95 delivery£36.90View ›
Prices from UK retailer feeds, updated daily.We may earn a commission
3.0AhCapacitymaker figure
36WhEnergymaker figure
0.2kgWeightmaker figure
180Wh/kgEnergy for its weightworked out
£9.98Per Ahat the lowest price we track

Other sizes in this range

Same fit, same tools. Bigger packs run longer and weigh more. Pick the size for the job.

Compare these sizes ›All Milwaukee M12 batteries ›
ModelSizeEnergyWeightLowest pricePer Ah
M12B2 2.0Ah 24Wh 0.2kg £25.95 £12.98 per Ah
M12HB2.5 2.5Ah 30Wh 0.2kg £32.95 £13.18 per Ah
M12B3 This one 3.0Ah 36Wh 0.2kg £29.95 £9.98 per Ah
M12B4 4.0Ah 48Wh 0.4kg £39.95 £9.99 per Ah
M12HB5 5.0Ah 60Wh 0.42kg £59.95 £11.99 per Ah
M12B6 6.0Ah 72Wh 0.4kg £49.95 £8.33 per Ah

Prices are the lowest we track at UK retailers, updated daily. Weights from Milwaukee. Energy is Milwaukee's figure, or worked out from volts × Ah where they don't publish one.

Full specs

From Milwaukee's own documentation, checked 27/09/2026. "Not listed" where Milwaukee doesn't publish a figure.

Voltage12V
Capacity3.0Ah
Energy36Wh
ChemistryLi-ion
Cell typeNot listed
Weight0.2kg
Size (L × W × H)Not listed
Fuel gaugeYes
ExtrasREDLINK Intelligence
PlatformMilwaukee M12
Model codeM12B3

Charge times

Milwaukee's own figures, fastest first. Each charger opens its own page.

M12-18FCMulti-voltage fast charger
50 min
£59.95 at Tooled Up ›
M12-18GBC4Four-bay gangbox charger (2 at once)
50 min
No retailer price yet
C12CCharger
1 hr 10 min
£44.95 at Tooled Up ›
M12C44-bay sequential charger
1 hr 10 min
£78.95 at Tooled Up ›
M12-18ACIn-car charger
1 hr 30 min
£79.95 at Tooled Up ›

Milwaukee's own figures. We may earn a commission

Fits these tools

Every Milwaukee M12 tool takes this pack. It won't fit other brands' tools.

All 35 Milwaukee M12 tools ›
Ratchets11 tools › Drill Drivers4 tools › Multi-Tools2 tools › Reciprocating Saws2 tools › Belt Files2 tools › Random Orbital Sanders2 tools › Combi Drills2 tools › Rotary Polishers1 tool › Detail & Delta Sanders1 tool › Mini & Spot Repair Sanders1 tool › Planers1 tool › Brad Nailers1 tool › Jigsaws1 tool › Handheld Vacuums1 tool › Site Vacuums1 tool › Angle Drills1 tool › Circular Saws1 tool ›

3.0Ah packs from other brands

Only useful if you haven't picked a platform yet: packs don't swap between brands. Shown on neutral figures only.

Not sure which platform? ›
BatteryEnergyWeightWh per kgLowest pricePer Ah
MilwaukeeM12B3 36Wh 0.2kg 180 £29.95£9.98
BoschGBA12V-30 36Wh 0.18kg 200 £55.00£18.33
DeWaltDCB124 32Wh 0.25kg 130 No price yet

M12B3 questions

Which tools does the M12B3 fit?

It fits every Milwaukee M12 tool. It won't fit other brands' tools.

How long does the M12B3 take to charge?

From Milwaukee's own figures: M12-18FC: 50 min, M12-18GBC4: 50 min, C12C: 1 hr 10 min, M12C4: 1 hr 10 min, M12-18AC: 1 hr 30 min.

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