How much does a concrete slab cost per square foot?

What the price data says

We pulled slab prices from three separate datasets. HomeAdvisor and Angi share one dataset, so we count them as one. HomeGuide and Homewyse are separate. Each defines "a slab" a little differently, so compare the scope before the number.

Source (date)	Installed price per sq ft	Typical total	What it assumes
HomeGuide (Feb 2026)	$6 to $12[1]	$5,400 to $10,800 for 30 x 30 ft[1]	4 to 6 in slab, basic finish
HomeAdvisor (Jun 2026)	About $6 average; $4 to $18 range[2]	$3,600 to $7,200, $5,400 average[2]	Thin slabs at the low end, thick foundations at the high end
Homewyse (Sep 2026)	$10.63 to $13.00[3]	n/a	Small basic slab, 4+ in, fiber reinforced, 3,500 psi, broom finish; no excavation, gravel base or demolition

Homewyse runs higher because its example is a small job with minimum labor and equipment costs built in^[3]. Small slabs carry setup costs that do not shrink with size, so expect a higher per square foot price on a 10 by 10 pad than on a large patio.

Cost by slab size

HomeGuide's size table uses its $6 to $12 range^[1]:

Slab size	Square feet	Installed cost
10 x 10 ft	100	$600 to $1,200
12 x 12 ft	144	$860 to $1,700
20 x 20 ft	400	$2,400 to $4,800
20 x 30 ft	600	$3,600 to $7,200
30 x 30 ft	900	$5,400 to $10,800
40 x 40 ft	1,600	$9,600 to $19,200

Cost by thickness

Thicker slabs use more concrete and labor. HomeGuide's installed prices^[1]:

Thickness	Cost per sq ft
4 in	$6 to $8
6 in	$8 to $10
8 in	$10 to $12

Most residential slabs are 4 to 6 inches thick^[1]. For which thickness fits a shed, hot tub or RV, see slab thickness by use.

Materials vs labor

Item	HomeGuide (Feb 2026)	HomeAdvisor (Jun 2026)	Fixr (Jan 2025)
Materials	$3 to $7 per sq ft[1]	n/a	n/a
Labor	$3 to $5 per sq ft[1]	$2 to $3 per sq ft[2]	n/a
Ready-mix concrete	n/a	About $110 per cubic yard[2]	$125 to $150 per cubic yard[4]

HomeGuide says labor is 40% to 50% of a slab's total cost^[1]. One cubic yard covers about 81 square feet of a 4 inch slab^[1].

Add-ons that change the quote

• Gravel base: $1 to $3 per square foot^[1].
• Leveling or grading: $0.40 to $2.00 per square foot^[1].
• Rebar: $1.40 to $1.85 per foot, per HomeAdvisor, which notes it is used to reinforce slabs thicker than 4 inches^[2]. See rebar vs wire mesh vs fiber.
• Removing an old slab: $3 to $8 per square foot including disposal, plus $1 to $3 per square foot more if it is reinforced^[5].
• Stamped finish: $8 to $19 per square foot installed, including the pour^[1].
• Sealing: $1 to $3 per square foot^[1].
• General contractor markup: Homewyse adds 13% to 22% if a general contractor supervises the job^[3].
• Permits: Homewyse leaves permit fees out of its estimate^[3]. Ask your city whether your slab needs one.

Why prices vary by region

National averages hide wide local swings. HomeAdvisor reports about $5.35 per square foot in central states versus up to $8.50 in coastal states such as California and New York^[2]. Labor rates, ready-mix prices, haul distance and access all move the number. Homewyse prices by ZIP code for this reason^[3].

Soil matters too. A slab on expansive clay, common in much of Texas, or on soft fill may need more base, more excavation or more reinforcement than a slab on firm, well-drained ground. Those items appear as add-ons, not in the base price per square foot.

How to compare quotes

• Check that each quote names the same thickness, base depth, reinforcement and finish.
• Ask whether excavation, demolition, forms and haul-away are included.
• Ask for the concrete strength in psi and, in freeze-thaw areas, whether the mix is air-entrained.
• Compare the per square foot price only after the scope matches.

When to call a pro

• Any slab that will carry a building, a vehicle or a hot tub, where thickness and base should be set by the contractor or a designer.
• Sites with clay soil, slopes or standing water, where base and drainage drive the price.
• Replacing an old slab, where a contractor in your area can tell you if removal, regrading or a new base is needed.