GardenCalc
The Short Answer
Topsoil costs roughly £10.40 to £13.00 per square metre at 5cm deep, going by six UK bulk-bag prices checked on 18 August 2026. Most people are not laying at 5cm though, so double it for 10cm and treble it for 15cm. A new lawn at the RHS minimum of 10cm is nearer £21 to £26 a square metre in bought topsoil.
The prices below are what the suppliers had on their own product pages on that date. They move, so treat this as the shape of the market rather than a quote.
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What Topsoil Costs, By Supplier
| Supplier and product | Size | Price | Cost per m² at 5cm |
|---|---|---|---|
| Wickes, Hallstone topsoil | 500 L | £109.00 | £10.90 |
| TurfOnline, topsoil bulk bag | 0.6 m³ (600 L) | £145.20 inc VAT | £12.10 |
| Rolawn, Turf & Lawn Seeding | 500 L | £129.99 | £13.00 |
| Rolawn, Turf & Lawn Seeding (large) | 750 L | about £164.99 | £11.00 |
| Rolawn, Blended Loam (large) | 750 L | £155.99 | £10.40 |
| B&Q, Flower Bed & Border Mix | 830 L | £179.95 | £12.00 |
All six checked on the suppliers' own product pages on 18 August 2026. The per-m² column is our own sum. Where the supplier states a coverage at 5cm we used that: Rolawn's 500 litre bag covers 10 square metres, its 750 litre bags and B&Q's 830 litre bag cover 15. Where no coverage is published, Wickes and TurfOnline, we divided the litres by 50, since a square metre at 5cm deep takes 50 litres. B&Q's bag holds more litres than 15 square metres needs, so going by their stated coverage rather than the litres is the honest figure and it is the dearer one. Wickes also lists three Rolawn 500 litre bags at £140 to £142, which is the same soil costing more through a third party.
A "bulk bag" is not a fixed size. The six above run from 500 to 830 litres, and the cheapest headline price is not the cheapest soil. Work out the price per litre or per square metre before you order, which is the whole reason the table has that last column.
How Much Topsoil Per Square Metre
The quantity is the easy bit. Multiply the depth in centimetres by 10 and you have the litres you need per square metre.
| Depth | Litres per m² | Rough cost per m² | Typical job |
|---|---|---|---|
| 2 cm | 20 L | £4 to £5 | Lawn top-dressing |
| 5 cm | 50 L | £10 to £13 | Levelling, light top-up |
| 10 cm | 100 L | £21 to £26 | New lawn, RHS minimum |
| 15 cm | 150 L | £31 to £39 | Borders, shallow-rooted veg |
| 20 cm | 200 L | £42 to £52 | New beds, RHS minimum |
| 30 cm | 300 L | £62 to £78 | Raised bed, shallow crops |
| 40 cm | 400 L | £83 to £104 | Root veg |
The cost column is the per-m² range from the supplier table above, scaled by depth. For an exact quantity on your actual shape, including odd corners, the topsoil calculator does it properly and gives you bags and tonnes as well as litres.
How Deep, By Job
Depth is where the money goes, so it is worth getting from a source rather than a guess.
- New lawn: the RHS says at least 10cm. Rolawn gives 100 to 150mm for turf or seed.
- Before you lay it: the RHS says dig or rotovate to 20cm for seed and 20 to 25cm for turf.
- New beds and borders: RHS says about 20cm or more. Rolawn gives 150 to 200mm for ornamental planting.
- Veg: Rolawn gives 150 to 200mm for shallow-rooted crops and 300 to 400mm for root veg.
- Raised beds: the RHS says at least 30cm for shallow crops and 45cm or more for most plants, and suggests filling with 7 parts topsoil to 3 parts organic matter to 2 parts sharp sand rather than topsoil alone.
That last one saves real money. Filling a deep raised bed with bought topsoil only is the most expensive way to do it, and it is not what the RHS recommends anyway. The raised bed calculator works out the fill by bed size.
Which Grade to Buy
The RHS splits topsoil into three grades, premium, general purpose and economy, judged on pH, phosphorus, potassium and magnesium. The British Standard behind the good stuff is BS 3882:2015, published on 30 April 2015 and still the current specification. Rolawn and TurfOnline both state their topsoil is analysed or tested to it.
Our take: pay for the graded soil where you are growing, so lawns, veg beds and borders. Use the cheap stuff for bulk filling and levelling where nothing has to root into it. Buying premium soil to fill a hole is money you could have spent on plants.
Where We'd Buy It
A builders merchant is usually better value per litre than a garden centre for anything above one bag, and they deliver on a lorry with a crane offload, which matters when the bag weighs the better part of a tonne. Travis Perkins topsoil bulk bags are the merchant option we point people at.
If you have a local soil supplier or a farm doing screened topsoil, ring them first. Loose tipped soil off a local yard is almost always cheaper per cubic metre than anything bagged, and you are keeping the money nearby.
Affiliate disclosure: the Travis Perkins link above is an affiliate link and helps fund GardenCalc at no extra cost to you. We only point at things we would use ourselves.
Frequently Asked Questions
Work Out Your Exact Quantity
Note on prices. Every price on this page was read off the supplier's own product page on 18 August 2026 and includes VAT where the supplier states it. Prices and delivery charges change without notice, so check before you order. The per-square-metre figures are our own arithmetic from those prices and the coverage each supplier publishes.