GardenCalc
The Short Answer
There are two completely different answers and mixing them up is how people overspend. Hot mix tarmac runs about £40 to £80 a tonne according to UK cost guides, and that is a supply-only rate: it does not include delivery, laying or compaction. Bagged cold lay macadam from a merchant works out at roughly £475 a tonne, because you are paying for 25kg at a time.
Bags are for potholes and patches. If you are surfacing anything the size of a drive, you want a load, not a pallet.
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Bagged Cold Lay: What It Costs
| Supplier | Product, 25kg | Price | Per tonne |
|---|---|---|---|
| Travis Perkins | Tarmac Cold Lay Macadam | £11.87 inc VAT | £475 |
| B&Q | Tarmac Cold Lay Ready Mixed Macadam | £11.97 | £479 |
| Wickes | Tarmac Cold Lay Macadam, major bag | £12.00 (10 for £108) | £480 (£432 on the deal) |
| Screwfix | Ultra Crete Pothole Repair, black | £33.79 inc VAT | £1,352 |
| Toolstation | Maxam Tarmax | £45.99 inc VAT | £1,840 |
| Jewson | Drive repair asphalt | price gated behind branch selection | not published |
Five published prices, each read off the supplier's own product page on 18 August 2026 and linked in the first column so you can check it. Jewson stocks the same class of product but puts the price behind a branch selection, so there is no figure to quote. The per tonne column is the bag price times forty. The three cheap rows are the same standard cold lay macadam. The Screwfix and Toolstation rows are premium permanent-repair products, which is a different job and a different chemistry, not a rip-off.
At 30mm compacted, and both Tarmac the manufacturer and Wickes the retailer state the same figure for the same product. That is two and a half bags per square metre, about £30 of material, at 30mm. Go to 40mm and the same bag covers about 0.3 square metres, so it is over three bags and nearer £40. A 20 square metre area at 30mm is fifty bags and roughly £600.
Hot Mix: What the Guides Say, and Why There Is No Price List
Here is something worth knowing before you trust a per tonne figure: the three big producers we checked do not publish one. Tarmac, Holcim UK and Heidelberg Materials all put asphalt behind a quote request on 18 August 2026. We did not check every plant in the country, so we are not going to claim none of them publishes a price. What we can say is that the figures below come from cost guides rather than a producer price list, and they should be read that way.
| Source | Per tonne | Stated coverage |
|---|---|---|
| MyBuilder (updated 10/12/2025) | £40 to £70 supply only | about 8 m² at 40mm |
| MyJobQuote | £45 to £60 supply only | about 8 m² |
| Classic Stone Driveways | £50 to £80 supply only | not stated |
| Squote | £85 to £140 supply only (wearing course) | about 10 m² at 50mm |
The four agree on the shape: base material in the forties to eighties, a finished wearing course dearer. Comparing at the same depth is the fair test, and the coverage figures themselves disagree. MyBuilder quotes 8 square metres a tonne at 40mm. Our own tarmac calculator works on a compacted density of 2,400 kg per cubic metre, which gives about 10.4 square metres a tonne at the same depth. Take both and hot mix comes out at roughly £4 to £10 a square metre in material. A 25kg bag covers 0.4 square metres at 30mm, so at 40mm it covers about 0.3, which is over three bags and roughly £40 a square metre. Bagged material lands somewhere around four to ten times the price of hot mix for the same layer.
What a Tarmac Drive Costs Fully Laid
Material is the small part. The trade directories put a finished drive at:
- Checkatrade, updated June 2026: about £50 a square metre materials only, about £90 a square metre fully installed, and about £4,500 for a 50 square metre drive.
- MyBuilder, updated 4 May 2026: £45 to £80 a square metre fully installed.
Both are guide figures published by directories that sell leads to tradespeople, not quotes, and they do not always agree with themselves. Treat them as a sanity check on the three real quotes you should be getting, not as a price.
Do not forget what goes underneath either. A drive needs a compacted sub-base before any tarmac goes down, and that is a separate material and a separate cost. The sub-base calculator works out the MOT Type 1 you need.
Bags or a Load? The Honest Rule
- Under about 2 square metres: bags. A plant will not deliver a part load and you cannot lay hot material quickly enough on your own anyway.
- A pothole or a patch: bags, and consider the premium permanent-repair products. They cost three or four times the standard cold lay and last accordingly.
- Anything drive-sized: a load, laid by someone with a roller. Hot material has to be spread and compacted before it cools, which is not a one-person afternoon.
- Check what is quoted: supply only, supply and lay, and supply and lay including excavation and sub-base are three very different numbers.
Frequently Asked Questions
Work Out Your Quantity
Note on prices. Bag prices were read off each supplier's own product page on 18 August 2026 and include VAT where the supplier states it. Per tonne and per square metre figures are our own arithmetic from those prices and the published coverage. Hot mix and installed-drive figures are published cost-guide estimates, not quotes, and are labelled as such throughout. Always get three written quotes for a drive.