Asphalt Road Cost per Kilometre — Tonnage and Budget
A 7.3 m wide carriageway needs about 848 tonnes of asphalt per kilometre for a 50 mm wearing course. This page gives tonnage per kilometre for every common carriageway width, construction and resurfacing costs per kilometre, and how the budget divides between pavement, earthworks and drainage.
Road asphalt tonnage calculator
Enter the carriageway as a rectangle — width in metres, length in metres — and add a second area for shoulders or a second layer. For 1 km enter 1,000 m length.
Asphalt tonnage per kilometre
| Carriageway | Width | Area per km | 50 mm | 100 mm | 150 mm | 200 mm |
|---|---|---|---|---|---|---|
| Single lane | 3.65 m | 3,650 m² | 424 t | 848 t | 1,272 t | 1,696 t |
| Two lanes | 7.3 m | 7,300 m² | 848 t | 1,696 t | 2,544 t | 3,392 t |
| Two lanes + shoulders | 11.0 m | 11,000 m² | 1,277 t | 2,555 t | 3,832 t | 5,110 t |
| Four lanes | 14.6 m | 14,600 m² | 1,696 t | 3,392 t | 5,087 t | 6,783 t |
| Four lanes + shoulders | 21.0 m | 21,000 m² | 2,439 t | 4,878 t | 7,317 t | 9,755 t |
| Six lanes divided | 24.0 m | 24,000 m² | 2,787 t | 5,575 t | 8,362 t | 11,149 t |
Dense-graded mix at 2,322.7 kg/m³, before any waste buffer. Add 8–10% for waste and for widening at curves, intersections and lay-bys.
Cost per kilometre
| Road type | New construction per km | Notes |
|---|---|---|
| Rural two-lane, flat terrain | $700,000 – $1,400,000 | Minimal earthworks, no land acquisition |
| Rural two-lane, rolling terrain | $1,200,000 – $2,500,000 | Significant cut and fill |
| Rural two-lane, mountainous | $2,500,000 – $8,000,000 | Rock excavation, retaining structures |
| Urban two-lane with kerbs and drainage | $2,000,000 – $4,500,000 | Utilities, drainage, traffic management |
| Four-lane divided rural | $3,000,000 – $6,000,000 | Median, wider structure |
| Four-lane divided urban | $5,000,000 – $15,000,000 | Land acquisition dominates |
| Motorway / interstate mainline | $6,000,000 – $20,000,000 | Full-depth, structures, interchanges separate |
These are US figures for the roadway itself. Bridges, interchanges, land acquisition and utility relocation are budgeted separately and frequently exceed the roadway cost on urban projects.
Cost by pavement structure
For a 1 km two-lane rural road, 7.3 m wide, the pavement layers alone:
| Layer | Thickness | Tonnage | Rate | Cost |
|---|---|---|---|---|
| Wearing course (dense HMA) | 50 mm | 848 t | $145/t | $122,960 |
| Binder course | 70 mm | 1,187 t | $120/t | $142,440 |
| Asphalt base course | 100 mm | 1,696 t | $105/t | $178,080 |
| Aggregate sub-base | 250 mm | 4,015 t | $28/t | $112,420 |
| Prime and tack coats | — | — | — | $9,500 |
| Placement labour and plant | 7,300 m² | — | $14/m² | $102,200 |
| Pavement subtotal | $667,600 |
Add earthworks, drainage, signage, markings, safety barrier and traffic management to reach the total project cost. On a straightforward rural alignment the pavement is typically 45–60% of the roadway cost; in rolling or urban terrain it falls to 25–35%.
International cost comparison
| Country | Two-lane rural, per km | Currency | Notes |
|---|---|---|---|
| United States | $700k – $1.4M | USD | Varies widely by state |
| Canada | CA$900k – CA$1.8M | CAD | Frost design adds structure |
| United Kingdom | £1.2M – £2.5M | GBP | High land and compliance costs |
| France | €700k – €1.5M | EUR | EME allows thinner structures |
| Germany | €900k – €1.8M | EUR | Heavy design standards |
| India | ₹25M – ₹60M | INR | Roughly $300k–$720k; lower labour cost |
| Pakistan | ₨120M – ₨300M | PKR | NHA specification |
| Australia | A$1.0M – A$2.2M | AUD | Long haul distances in remote areas |
Direct comparison is difficult because scope definitions differ — some jurisdictions include drainage and earthworks in the per-kilometre figure and others do not. Treat these as orders of magnitude.
Where the money goes
| Component | Rural share | Urban share |
|---|---|---|
| Pavement (all layers) | 45–60% | 25–35% |
| Earthworks | 15–25% | 5–15% |
| Drainage | 8–15% | 15–25% |
| Utility relocation | 0–3% | 10–25% |
| Traffic management | 2–5% | 8–15% |
| Signage, markings, barrier | 4–8% | 5–10% |
| Design and supervision | 6–10% | 8–12% |
Resurfacing costs
| Treatment | Per km (7.3 m wide) | Per m² | Life extension |
|---|---|---|---|
| Crack sealing | $8,000 – $20,000 | $1.10 – $2.75 | 2–4 years |
| Fog seal | $11,000 – $22,000 | $1.50 – $3.00 | 3–5 years |
| Chip seal | $30,000 – $60,000 | $4.10 – $8.20 | 5–8 years |
| Micro-surfacing | $45,000 – $85,000 | $6.20 – $11.60 | 6–9 years |
| Thin overlay (30 mm) | $130,000 – $220,000 | $17.80 – $30.10 | 8–12 years |
| Mill and overlay (50 mm) | $250,000 – $450,000 | $34.20 – $61.60 | 12–18 years |
| Full-depth reclamation | $400,000 – $750,000 | $54.80 – $102.70 | 20+ years |
| Full reconstruction | $700,000 – $1,400,000 | $95.90 – $191.80 | 25+ years |
The economics of pavement management sit in this table. A crack seal at $15,000 per km applied at the right moment defers a $350,000 mill-and-overlay by several years. Deferring the crack seal turns it into a $600,000 reclamation. This is why agencies with disciplined preventive maintenance programmes carry lower lifecycle costs than those that only respond to visible failure.
Frequently asked questions
How much does it cost to build 1 km of asphalt road?
For a two-lane rural road roughly 7.3 m wide, $700,000 to $1.4 million per kilometre in the US for new construction, or $250,000–$450,000 per km for a resurfacing. Costs vary enormously with terrain, earthworks and land acquisition.
How much asphalt is needed for 1 km of road?
A 7.3 m wide carriageway with a 50 mm wearing course needs about 848 tonnes, or 933 tonnes with a 10% buffer. A full structure with binder and base courses needs three to four times that.
What is the cost per km of highway?
A four-lane divided highway typically runs $3–$8 million per kilometre in the US including earthworks, drainage and structures. Urban sections with land acquisition and utility relocation can be several times higher.
How much does road resurfacing cost per km?
$250,000 to $450,000 per kilometre for a mill-and-overlay on a two-lane road, assuming the underlying structure is sound. This is the most common highway maintenance activity by volume.
Why do road costs vary so much between countries?
Labour rates, land acquisition, environmental and permitting requirements, terrain, and design standards. The physical asphalt is a minority of the total on most projects — earthworks, drainage and structures dominate.
How do you calculate road asphalt tonnage?
Multiply the carriageway width by the length to get area, then apply the standard tonnage formula for each layer thickness. Add shoulders separately if they are paved, and allow for widening at curves and intersections.
Sources and further reading
- FHWA — Federal Highway Administration
- AASHTO
- Transportation Research Board
- MoRTH — Ministry of Road Transport & Highways, India
- National Highways (UK)
Pricing data period: Q3 2026 (July–September)
Sources: US Bureau of Labor Statistics Producer Price Index series for asphalt paving mixtures and blocks, cross-checked against regional contractor quotations and published state DOT bid tabulations.
Update cadence: monthly, on the fifth business day.
Scope: United States. Prices exclude sales tax and are plant-gate unless stated as installed.
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