Concrete Slab Cost Calculator
Concrete slab cost runs about $4,017 for a 20 by 20 in Atlanta at 4 inches, or $1,456 for a 10 by 10 and $8,393 for a 30 by 30. The figure worth understanding is not the total: it is that the concrete itself is only 26% of the bill. The rest is base, forms, steel and the hours to place and finish it.
Estimate the cost for your home
Estimated cost of the finished slab
$4,271
typical · range $3,413 to $5,129 · 400 sq ft · $10.68 per sq ft · 5.3 cu yd of concrete
Labour priced at national wages. Enter a ZIP code to price it for your area. 56% of this figure comes from modelled material prices — each line shows its own uncertainty.
Priced from fema.gov Aug 2026bls.gov Aug 2026and 1 more, all listed below
The one input that changes the answer for you.
The standard for a patio, a walkway or a shed base. Fine for foot traffic and garden furniture, not for a vehicle.
A sheet of mesh lifted into the middle of the pour. It does not stop cracks; it holds the two sides of a crack together, which is a different and more useful thing.
Dragged with a broom for grip once it has set enough. The default, the cheapest, and the right answer outdoors where it rains.
The mixer backs up and the concrete runs down the chute. Cheapest by a distance, and the reason a front driveway costs less than a back garden of the same size.
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The figure above is already calculated. Each step just makes it more yours, and you can stop at any of them.
Where the money in a slab actually goes
The material that gives the job its name is the minority of the bill.
- Concrete
- 25%
- Base, forms, steel and curing
- 19%
- Placing and finishing hours
- 36%
- Excavation and haulage
- 20%
At 5.3 cubic yards, the concrete is 25% of this figure. That is why two quotes for the same slab can differ so much: they are not disagreeing about concrete, they are disagreeing about everything else.
| Line item | Qty | Cost | Source |
|---|---|---|---|
| Ready-mix concrete, deliveredarea × thickness ÷ 12 ÷ 27 × 1.08 | 5.33cubic yard | $827–$1,280 | estimated±22% |
| Compacted gravel basearea × base depth ÷ 12 ÷ 27 × 1.25 for compaction | 6.17cubic yard | $235–$525 | estimated±38% |
| Formwork, stakes and releaseslab perimeter | 80linear ft | $112–$288 | estimated±44% |
| Welded wire mesh and chairsslab area where mesh is used | 400sq ft | $112–$260 | estimated±40% |
| Compact excavator1 h + 1 h per 200 sq ft where the site is excavated | 3hour | $171–$171 | sourced |
| Equipment operatorsame hours as the machine | 3hour | $168–$180 | sourced |
| Haul away the spoilarea × (slab + base depth) ÷ 12 ÷ 27 × 1.25 swell | 12.3cubic yard | $272–$741 | estimated±46% |
| Labourer: grade, compact, set forms and place steel3 h + 1 h per 30 sq ft (modelled) | 17hour | $748–$804 | sourced |
| Cement mason: place, screed, float and finish2 h + area × finish rate, ×1.4 on a wheelbarrow run (modelled) | 11hour | $585–$629 | sourced |
| Cement mason: cut the control joints1 h + 1 h per 250 sq ft where joints are cut | 3hour | $160–$172 | sourced |
| Curing compound and protectionslab area | 400sq ft | $24–$80 | estimated±54% |
| Total | $3,413–$5,129 | ±20% |
Where these numbers come from
- Labour rates by area
- BLS Occupational Employment and Wage Statistics, May 2025, for cement masons, labourers and equipment operators. Retrieved 2026-08-20. Cement masons are published in 457 of the 530 areas in our index; in the rest that hour falls back to the broader construction group for the same area. Benefit load from BLS Employer Costs for Employee Compensation.
- Why breaking concrete is not the cheap part
- Cutting, grinding or breaking out concrete is respirable crystalline silica work, covered by OSHA 1926.1153, Respirable crystalline silica, which sets a permissible exposure limit and requires a written exposure control plan and a competent person to inspect the job. In practice that means water-fed or vacuum-shrouded tools rather than a dry saw and a dust cloud — see also OSHA, Crystalline Silica. Both retrieved 2026-08-22.
- A slab changes where the rain goes
- Every square foot of slab is a square foot that no longer absorbs water, and some jurisdictions cap how much of a lot may be covered for exactly that reason. EPA, Soak Up the Rain sets out the case for handling rainwater on the ground it falls on. Grading and drainage around the slab are not priced here, and on a slab next to a house they are worth thinking about before the pour rather than after. Retrieved 2026-08-22.
- What the quantities assume
- Concrete is area × thickness ÷ 12 ÷ 27 plus 8% over, because nobody orders the exact figure — a pour that runs short is a cold joint through the middle of the slab. Base stone is ordered 25% over its finished volume because it compacts. Both of those margins are our estimate, and they are the numbers to query first if you think the figure is wrong.
- Material prices
- Modelled estimates, not sourced prices. No public, machine-readable source of US residential material prices exists, and we would rather say so than pretend otherwise. Each line carries its own uncertainty band. How we estimate them.
Contractor overhead and profit applied at 33–43% over direct cost. Data last reviewed 2026-08-22.
What this figure does not include
- What the concrete alone costs delivered
- This page prices a finished slab. If what you want is the material at the kerb — a yard of ready-mix, the short-load fee under about four yards, the delivery and the waiting time — that is a different question and it has its own page. The two are deliberately not the same number.
- Permits and inspections
- A patio rarely needs one; a slab that will carry a structure usually does, and in many places it has to be inspected before the pour rather than after. Fees vary by jurisdiction with no national source and are excluded rather than averaged.
- Footings and foundations
- A slab that carries a wall needs a thickened edge or a separate footing below the frost line, and how deep that is depends on where you live. That is foundation work, it is designed rather than estimated, and it is not in these figures.
- Drainage and where the water goes
- A slab is an impervious surface, and adding one changes where rain ends up. Some jurisdictions limit how much of a lot can be covered. See the EPA on managing rainwater on your own ground. Grading the surroundings is not priced here.
- Ground that is not ordinary
- Expansive clay, fill, a high water table or tree roots through the pour area all change the base design, and sometimes require an engineer. This models a straightforward dig into stable ground.
- Sealing on a cycle
- Stamped and coloured concrete needs resealing every few years to keep looking like the photograph. That is a cost of ownership rather than of installation.
Questions people actually ask
How much does it cost to pour a 20x20 slab of concrete?
About $4,017 in Atlanta for a 4-inch slab with a compacted base, wire mesh, a broom finish and cut control joints, in a range of $3,168 to $4,866. That is 10.04 a square foot and 5.3 cubic yards of concrete ordered. The number worth carrying away is that the concrete is only 26% of it. Take it to 6 inches with a rebar grid, which is what a slab a vehicle will sit on wants, and it comes to $4,864.
How much does it cost to have a 10x10 concrete slab poured?
About $1,456 in Atlanta, which is 14.56 a square foot — considerably more per foot than a 20 by 20 at 10.04. Small slabs are dear per square foot and it is not a markup: the truck, the crew and the set-up cost the same whether they pour a hundred square feet or nine hundred, and at 100 square feet you are ordering barely over a yard of concrete, which brings its own short-load surcharge from the plant. If there is anything else you want poured, pouring it the same day is close to free by comparison.
How much does a 30x30 concrete slab cost?
About $8,393 in Atlanta at 4 inches with mesh and a broom finish, which works out at 9.33 a square foot and 12.0 cubic yards of concrete. At this size the per-foot rate is close to as good as it gets, because the fixed costs are spread over 900 square feet. What changes the figure most from here is not the size but the specification: thickness, whether there is rebar rather than mesh, and the finish. A stamped and coloured finish on the same 20 by 20 slab, for comparison, takes it from $4,017 to $5,266.
Is it worth it to pour your own concrete slab?
The honest answer starts with what you would actually be saving, and it is not the concrete: the concrete costs the same whoever orders it. On this 20 by 20 slab the material is 26% of the bill and the rest is base, forms, steel and hours. So the question is whether you want to do the hours. Two of them are worth thinking about separately. The preparation — digging, grading, compacting, setting forms, tying steel — is slow, heavy and forgiving of a beginner. The finishing is neither: concrete sets on its own schedule, and a first-timer who is still floating when it goes off has bought one surface for the next thirty years. Plenty of people pour their own shed base. Rather fewer are pleased with their own garage floor.
Taken from Google’s “people also ask” results for this search on 22 August 2026, not invented.
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- The full concrete slab cost dataset
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- How we calculate
The formula, the sources, and an honest account of which parts of the model are weak.