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SlabCosts
Prices updated January 2026

Concrete Slab Cost

What a concrete slab really costs in 2026 — per square foot and for your exact size, materials or fully installed.

Installed by a pro, a plain 4" concrete slab costs about $6–$12 per square foot in 2026. Materials only (DIY) run far less. Enter your size below for the full breakdown.

Concrete slab cost calculator

Waste & region

Order extra for spillage & uneven subgrade. 10% is typical.

Installed cost estimate

$2,200 – $4,800

400 sq ft · 5.43 yd³ concrete

Bags of concrete needed (rounded up)

245

80 lb

326

60 lb

392

50 lb

489

40 lb

Ready-mix (delivered)
$739 – $1,207
Bagged mix (80 lb, DIY)
$1,348 – $2,205
Installed by a pro
$2,200 – $4,800

Estimate only — not a quote. Bag counts are rounded up and include a 10% waste allowance.

Installed $2,200 – $4,800

Concrete slab cost per square foot (installed)

Slab thickness Cost / sq ft 400 sq ft (20×20)
4" slab $6 – $12 $2,200 – $4,800
5" slab $6 – $13 $2,500 – $5,100
6" slab $7 – $14 $2,800 – $5,400

National US averages, January 2026. Regional pricing adjusts under "Waste & region" in the calculator.

You'll also need

Sized for this exact slab — tap any item to open its calculator with your measurements already filled in.

Gravel base

5.68 yd³

4" compacted base under the slab

≈ $170 – $369

Open calculator
Rebar

28 sticks

#4 bar, 18" grid (28 bars)

≈ $196 – $364

Open calculator
Bedding sand

1.24 yd³

~1" leveling layer

≈ $35 – $72

Open calculator

Concrete slab cost by size

Jump to a common size for its full materials-and-installed breakdown.

10×10 patio / shed 12×12 patio 20×20 two-car garage 24×24 two-car garage 30×40 shop / pole barn 40×60 commercial pad
4×4 8×8 8×10 10×10 10×12 10×20 12×12 12×16 12×24 14×14 15×15 16×16 16×20 18×20 20×20 20×24 20×30 20×40 24×24 24×30 24×40 25×25 30×30 30×40 30×50 30×60 40×40 40×50 40×60 40×80 50×50 1,000 sq ft 1,500 sq ft
Prices updated January 2026 National US averages · reviewed quarterly

Volumes use standard bag yields and a 10% waste allowance; costs are national US averages that vary by region, mix and finish. See our methodology for exactly how each figure is worked out, or check the reference sources:

Slab cost by project

Concrete Slab Cost Cost per sq ft + calculator Garage Slab Cost Typical 20×20 / 24×24 Driveway Slab Cost Concrete vs asphalt Patio Slab Cost 10×10 to 20×20 Shed Base Cost Small pads

Frequently asked questions

How much does a concrete slab cost?
Installed by a contractor, a standard 4" concrete slab costs about $5.50–$12 per square foot in 2026, including forming, pour, finish and basic prep. A 20×20 (400 sq ft) slab therefore runs roughly $2,200–$4,800 installed. Thicker or reinforced slabs cost more.
How much does it cost to pour a concrete slab yourself?
DIY, you're mainly paying for materials. A 20×20 4" slab needs about 5.4 cubic yards — roughly $740–$1,200 in ready-mix delivered, or more in bags — plus gravel, rebar, forms and tools. You save the labor but it's heavy, time-critical work.
What affects the cost of a concrete slab?
Thickness, square footage, rebar/mesh, site prep and grading, finish (broom, stamped, colored), removal of an old slab, and your region. Remote sites and small pours cost more per square foot.
Is it cheaper to pour concrete or lay pavers?
A plain poured slab is usually cheaper per square foot than pavers, which carry higher material and labor costs. Pavers win on repairability and looks. Use the calculator to price the slab, then compare.