How much does a concrete slab cost in 2026?
HomeGuide (February 2026) puts a concrete slab at $6 to $12 per square foot installed on average, with a 4-inch slab at $6–$8 and a 6-inch slab at $8–$10 per square foot. This calculator prices complete projects, which run higher per foot: the installed ranges below carry the gravel base, reinforcement, thicker sections, a permit allowance and the fixed costs that weigh heaviest on small pours. These are planning ranges — your local quote may sit anywhere within or slightly outside this band depending on regional labor, season, and quarry distance.
What the per-square-foot price includes
A slab is built in layers, and knowing them helps you compare bids line by line:
- Base — 4 in of compacted gravel under the slab. Skipping it is the #1 cause of early cracking and heave.
- Forms and layout — lumber forms, square-up, and elevation set for drainage slope.
- Reinforcement — welded wire mesh ($0.59–$1.00 per sq ft in this calculator) for patios and walks; a #4 rebar grid for anything that carries vehicles, at $0.55–$0.95 per linear foot of bar (a 16-inch grid uses about 1.5 ft of bar per square foot).
- Concrete — the mix itself, typically 3,000–4,000 PSI for residential flatwork, 4 in thick for patios and 5–6 in where vehicles park.
- Finishing — screed, float, broom or trowel finish, and control joints sawn or tooled on an 8–12 ft grid so the slab cracks where it is told to.
- Curing — compound or wet cure; concrete reaches working strength over days, not hours.
Decorative work — stamping, integral color, exposed aggregate, polishing — is priced on top of this base assembly and can add 50–100% to the flatwork price depending on pattern complexity. Get decorative finishes quoted as a separate line so you can see the premium.
DIY pour or hire a crew?
Concrete is unforgiving of slow hands: once the truck starts discharging, a 400 sq ft pour gives a two-person crew about an hour of workable time to screed, float, edge, and joint. Small pads — a grill pad, a 4x4 stoop, a mower ramp — are honest DIY projects with bagged mix. A patio, driveway, or garage slab is crew work, and the line items you'd save (labor) are smaller than the cost of a failed pour that has to be broken out and hauled away.
If you want to cut cost with sweat instead of risk: do the excavation, base compaction, and forming yourself to your contractor's spec, then let their crew handle mix day. Many flatwork contractors will price that split.
Frequently asked questions
How much does a concrete slab cost in 2026?
HomeGuide puts a concrete slab at $6-$12 per square foot installed on average (February 2026). Complete projects price higher per foot once the gravel base, reinforcement, permit and fixed costs are counted, especially on small pours. In this calculator a 10x10 ft patio, 4 in thick with wire mesh, costs about $1,900-$3,100. A 20x20 ft garage slab, 6 in thick with rebar, costs $5,000-$8,100. A 24x24 ft garage slab at the same spec runs $6,700-$10,900. Thicker slabs and decorative finishes (stamped, colored, polished) push the price higher.
How thick should a concrete slab be?
Patios and walkways: 4 in. Driveways and garage floors: 4 in for cars, 5-6 in for heavier vehicles; the garage and driveway rows on this page use 6 in with rebar. Foundation slabs: 4-6 in with rebar. Always include a 4 in compacted gravel base under the slab.
Do I need rebar or wire mesh in a concrete slab?
Welded wire mesh is fine for patios and walkways; this calculator prices it at $0.59-$1.00 per square foot. Driveways, garages, and any slab supporting weight should use rebar in a grid. Number 4 bar runs $0.55-$0.95 per linear foot, and a 16-inch grid uses about 1.5 ft of bar per square foot. Fiber-reinforced mixes can substitute for mesh in some thin slabs.
How do I calculate cubic yards of concrete?
Multiply length (ft) × width (ft) × thickness (ft, divide inches by 12). Divide by 27 for cubic yards. Add 10% waste.
How much does a 30x40 concrete slab cost?
A 30x40 (1,200 sq ft) shop slab, 8 in thick with a rebar grid and difficult site prep, runs $20,300-$33,400 installed in this calculator, about $17-$28 per sq ft. At its default garage spec (6 in, rebar, easy site prep) the same 30x40 slab runs $12,900-$20,600, about $11-$17 per sq ft. That default band overlaps and extends above HomeGuide's $6-$12 per sq ft, and the shop example sits above it. Both include the gravel base, vapor barrier, rebar, a permit allowance and the calculator's fixed charges; HomeGuide gives broad material and labor bands, not a component-by-component estimate for these exact configurations, so this comparison does not establish what causes the difference. Shop slabs often also need higher-PSI mix and thickened edges for future walls, which add more.
How long before you can drive on a new concrete slab?
Keep foot traffic off for 24-48 hours, passenger vehicles off for about 7 days, and heavy vehicles off for 28 days, when standard mixes reach design strength. Cold weather stretches every one of those numbers - curing is chemistry, and the chemistry slows below about 50 F.
Is a concrete driveway better than asphalt?
Concrete costs more upfront but lasts 30-40 years with minimal upkeep; asphalt is cheaper to install but needs sealcoating every few years and resurfacing sooner. In hot climates concrete resists rutting; in extreme freeze-thaw regions asphalt tolerates movement better. Compare both with our asphalt driveway calculator.
