How much does a concrete slab cost?
Typical US ranges from cost guides reviewed in 2025–2026: a plain, broom-finished 4 in. slab costs roughly $4 to $9 per square foot when a contractor pours it. With this calculator's example prices, DIY materials come to roughly $4 to $7 per square foot (those DIY figures come from the calculator, not from a survey). Stamped or colored finishes, tight access, old concrete to remove and high local labor rates can push the installed price past $15 per square foot. Prices also vary 30–50% or more by region, season and contractor, so treat every figure here as a planning number, not a quote.
The calculator above uses editable example prices. Change each one to match what your local concrete plant, supplier and contractors actually quote you.
How the estimate works
Ready-mix cost = cu yd × price per yard + delivery or short-load fee
Bagged cost = bags (cu ft ÷ 0.6, rounded up) × price per 80 lb bag
Gravel base = length × width × (base in ÷ 12) × 1.15 ÷ 27 × price per yard
DIY total = concrete + gravel + reinforcement + forms and tools + removal + permit
Pro total = area × installed price per sq ft + removal + permit
The DIY total counts materials and the small items you must buy. It does not pay you for your time, and it leaves out tool rentals you have not entered. The professional price per square foot normally covers excavation, base, forms, labor, finishing and cleanup, but not demolition or permits.
Worked example: a 12 × 12 ft slab, 4 in. thick
These are the calculator's default inputs: ready-mix at $145 per cubic yard with a $150 delivery fee, a 4 in. gravel base at $50 per yard, wire mesh at $0.60 per square foot, $150 for forms and finishing tools, and a professional price of $8 per square foot.
- Area: 12 × 12 = 144 sq ft.
- Concrete: 144 × (4 ÷ 12) = 48 cu ft. With 10% waste, 52.8 cu ft, which is 52.8 ÷ 27 = 1.9556 cu yd (about 1.96).
- Ready-mix: 1.9556 × $145 = $283.56, plus the $150 fee = $433.56.
- Gravel base: 144 × (4 ÷ 12) × 1.15 = 55.2 cu ft = 2.0444 cu yd, × $50 = $102.22.
- Wire mesh: 144 × $0.60 = $86.40. Forms and tools: $150.
- DIY total: $433.56 + $102.22 + $86.40 + $150 = $772.18, or $5.36 per sq ft.
- Professional total: 144 × $8 = $1,152.00.
If you mix 80 lb bags instead, the same slab needs 88 bags (52.8 ÷ 0.6) at $6.50 each, or $572.00 for the concrete. That raises the DIY total to $910.62. In this example the delivery fee is still outweighed by the cost of the bags.
Concrete slab cost ranges
These are planning ranges for a plain slab, rounded from the overlap of published figures. Where sources disagreed widely, the high column is intentionally broad.
| Tier | Installed price per sq ft | 12 × 12 ft slab (144 sq ft) | 20 × 20 ft slab (400 sq ft) |
|---|---|---|---|
| Budget (easy access, plain finish) | $5 | $720 | $2,000 |
| Typical | $8 | $1,152 | $3,200 |
| High (decorative finish, hard access, extra prep) | $14 or more | $2,016 | $5,600 |
Other published figures to plug into the calculator: delivered ready-mix commonly runs about $125 to $175 per cubic yard, an 80 lb bag of premixed concrete sells for roughly $6 to $10 depending on the retailer, and breaking up and hauling away an old slab is often quoted at $2 to $6 per square foot. Reinforcement prices vary widely by supplier and by whether the figure includes installation, so ask your supplier. The calculator's mesh and rebar presets are our own rough estimates of DIY material cost.
What drives the cost
- Thickness. Going from 4 in. to 6 in. adds 50% more concrete, though the installed price per square foot rises by less than that because labor stays similar.
- Finish. A broom finish is cheapest. Stamping, stain and exposed aggregate can multiply the price two to three times.
- Site access. If a truck cannot reach the forms, a pump or extra labor with wheelbarrows adds cost.
- Base and drainage. Poor soil, slopes and frost-depth requirements mean more excavation and gravel.
- Small jobs. Ready-mix plants charge delivery or short-load fees on small orders, which can double the per-yard cost on a small slab.
- Removal and permits. Old concrete, dump fees, and any permit or inspection are extra.
- Region and timing. Labor and material prices differ by metro area, and many contractors are busiest and priciest in summer.
DIY or hire a pro?
A small, flat slab is a realistic first concrete project if you have help. The hard parts are timing and finishing: once concrete is placed, you have a limited window to level, float and finish it before it sets, and mistakes are expensive to undo. Bagged concrete spreads that pressure out, but mixing 60 or more bags by hand is hard physical work. For anything over about one cubic yard, ready-mix delivery is usually easier and gives a more consistent pour.
Hire a pro for large slabs, driveways, slabs attached to a house, anything with footings or structural loads, and sloped or poorly drained sites. Slabs can have code requirements for thickness, reinforcement, depth below frost and permits, so check with your local building department before you dig, and call 811 so buried utilities are marked. Wet concrete burns skin, and cutting or breaking old concrete creates silica dust, so use gloves, eye protection and a suitable respirator. Cracks, scaling and settling from a bad base are the most common reasons a slab fails early.
How to save money on a slab
- Get at least three written quotes and ask exactly what each includes: base, forms, reinforcement, finish, sealer, removal and cleanup.
- Call two or three ready-mix plants and ask about price per yard, delivery fees and short-load charges. Prices differ more than most people expect.
- Do the prep yourself: remove sod, dig to depth, set forms and lay the gravel base, then have a contractor pour and finish.
- Choose a plain broom finish and add color or stamping later with a sealer or stain if you want it.
- Keep the slab as thin as the use allows. A 4 in. slab is normal for patios and walkways, and only driveways and heavy loads need 5 to 6 in.
- Combine pours. One larger delivery is cheaper per yard than two small ones.
- Schedule in the off-season when contractors are less busy, avoiding freezing and extreme heat.
Where these numbers come from
The contractor price ranges above are rounded from published consumer cost guides reviewed in 2025–2026 (including LawnStarter and RemodelAI), and the ready-mix figures from published ready-mix price ranges. The DIY materials presets (gravel base, reinforcement, forms and tools) and the flat allowances are our own rough estimates, not survey figures. Sources disagree, so the installed defaults sit in the middle of the overlapping ranges, rounded. For exact quantities of concrete and bags, use the concrete calculator, and for the base use the gravel calculator.
Frequently asked questions
How much does a 20x20 concrete slab cost?
A 20 × 20 ft slab is 400 sq ft. At 4 in. thick with 10% waste it needs about 5.43 cubic yards. With the calculator's example prices, DIY materials come to about $1,612 with ready-mix ($4.03 per sq ft) or about $2,266 with bagged mix, and a professional install at $8 per sq ft is $3,200. Published ranges of roughly $4 to $9 per sq ft would put a contractor-poured slab between $1,600 and $3,600.
How much does a 10x10 concrete slab cost?
A 10 × 10 ft, 4 in. slab is 100 sq ft and needs about 1.36 cubic yards with waste. With the example prices, DIY materials are about $628 with ready-mix or $684 with bags, and a professional install at $8 per sq ft is $800.
Is ready-mix concrete cheaper than bagged concrete?
Usually, once you need more than about a cubic yard. For a 12 × 12 ft slab the example concrete costs $433.56 delivered versus $572 in bags. With the example prices the break-even is about one cubic yard of concrete (roughly an 8 × 8 to 9 × 9 ft slab at 4 in. with 10% waste), and below that bags usually win because the delivery or short-load fee dominates. Ask your plant for its fees.
How much does it cost to remove an old concrete slab?
Published estimates vary. A common quote is about $2 to $6 per square foot including hauling away the debris, with minimum charges on small jobs. Thick, reinforced or hard-to-reach concrete costs more. Enter the area and your quoted price in the removal fields.
Does a concrete slab need rebar or wire mesh?
Not always, but many residential slabs use wire mesh or rebar to help hold cracks tight. Requirements depend on the slab's use, soil and local code, so check with your building department. Reinforcement prices vary widely by supplier and by whether installation is included, so ask for current prices. The calculator's presets are our own rough estimates of DIY material cost.
How much more does a thicker slab cost?
A 6 in. slab uses 50% more concrete than a 4 in. slab. One published guide (LawnStarter) puts a 4 in. slab around $5.35 per sq ft and a 6 in. slab around $6.19, so the installed price rises much less than the concrete volume. Ask contractors to quote your thickness.
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