How many litres are in a bulk bag of topsoil?

Last reviewed 1 July 2026

Short answer

Most UK topsoil bulk bags hold 700–800 litres, commonly quoted as 730 L or 0.73 m³. One cubic metre is 1,000 litres, so a bulk bag is roughly three-quarters of a cubic metre. Always check the stated volume — bags vary between suppliers and the difference across a multi-bag order is significant.

Work it out for your project with the topsoil calculator

Litres, cubic metres and bags

Volume equivalents
VolumeLitresCubic metresBulk bags at 730 L25 L bags
1 bulk bag7300.73129
1 cubic metre1,0001.001.440
1 cubic yard7650.7651.0531
Raised bed 2.4 × 1.2 × 0.4 m1,1521.151.646

Why soil is sold by volume and gravel by weight

Aggregate has a fairly predictable density, so weight is a reliable proxy for how much material you get. Topsoil does not: the same soil can be 1,100 kg/m³ after a dry fortnight and 1,500 kg/m³ after heavy rain.

Selling soil by weight would mean the buyer pays for water. Selling it by volume means the buyer gets a predictable amount of ground covered, which is what they actually care about.

This is why a 'one tonne bag' of aggregate and a 'bulk bag' of topsoil are different things, and why comparing them by name gets people into trouble.

Converting a bed into bags

Work out the volume in litres, then divide by the bag volume and round up.

A raised bed 2.4 m × 1.2 m internal, filled to 400 mm, is 2.4 × 1.2 × 0.4 = 1.152 m³, or 1,152 litres. Add 20% for settlement and you need 1,382 litres — two 730 L bulk bags, or 56 bags of 25 litres.

The 25-litre bag comparison is instructive: 56 bags is an entire car boot several times over, and usually costs far more than two bulk bags.

Handling a bulk bag

  • A 0.73 m³ bag of topsoil weighs around 950 kg. It cannot be moved by hand once it is on the ground.
  • The delivery lorry needs to place it where you want it. Decide before it arrives, and make sure the ground there is firm and level.
  • Cut the bag down the side rather than opening the top, so the soil slumps out instead of having to be dug upwards.
  • Empty it promptly. A bulk bag left on a lawn kills the grass under it in a couple of days.