2026 planning guide
How Much Does a Concrete Slab Cost?
A basic four-inch residential concrete slab has a starting planning range of $4 to $8 per square foot. That range assumes a straightforward slab before unusual excavation, engineering, difficult access, demolition, thickened edges, specialty reinforcement, or decorative finishes.
Installed cost estimator
Estimate your concrete slab cost
Enter the slab dimensions. For projects from 100 to 1,500 square feet, the result applies the sourced four-inch baseline used in this guide. It is not a local contractor quote.
Common slab sizes
Four-inch baseline for 100 sq ft
$400 to $800
$4 to $8 per square foot
This arithmetic baseline assumes a basic four-inch slab. It does not price minimum charges, demolition, difficult access, grading, pumping, permits, engineering, thickened edges, reinforcement, or decorative finishes.
Your dimensions will carry into the project request.
What does the $4 to $8 slab range include?
Contractors for Concrete uses $4 to $8 per square foot as a starting national planning range for a basic installed four-inch residential slab. It is useful for early budgeting, but it is not a promise that every small pad, patio, driveway, garage floor, or foundation can be completed at that rate.
Reasonable baseline
Straightforward access, simple shape, basic finish, and ordinary preparation within the contractor's standard scope.
Commonly extra
Demolition, hauling, pumping, difficult grading, permits, engineering, thickened edges, moisture systems, and decorative work.
Why small slabs vary
Minimum labor, delivery, short-load, equipment, and mobilization charges can make a small slab cost more per square foot.
Concrete slab cost examples by size
These examples multiply slab area by the shared four-inch planning range. They show the arithmetic baseline, not a guaranteed contractor minimum or complete project quote.
| Slab dimensions | Area | Four-inch baseline before minimum charges |
|---|---|---|
| 10 × 10 feet | 100 square feet | $400 to $800 |
| 12 × 12 feet | 144 square feet | $576 to $1,152 |
| 12 × 20 feet | 240 square feet | $960 to $1,920 |
| 20 × 20 feet | 400 square feet | $1,600 to $3,200 |
| 24 × 24 feet | 576 square feet | $2,304 to $4,608 |
How does slab thickness change the planning range?
Thickness increases concrete volume, but it does not create a reliable universal price adjustment because labor, preparation, reinforcement, edges, and placement conditions also affect the quote. The required thickness should come from the project use, loads, support, local requirements, approved plans, or project-specific design.
| Planned thickness | Concrete volume compared with 4 inches | How to use it |
|---|---|---|
| 4 inches | Baseline volume | Use the sourced $4 to $8 range only for a basic four-inch slab. |
| 5 inches | 25% more concrete volume | Ask the contractor to price the specified section. Do not add 25% to the entire quote. |
| 6 inches | 50% more concrete volume | Ask the contractor to price the specified section. Labor and other scope costs do not rise in the same proportion. |
Use the concrete slab thickness guide to understand the decision inputs before pricing a thickness.
Which scope items can move the slab price?
| Scope item | Why it changes cost | What to confirm |
|---|---|---|
| Demolition and disposal | Saw cutting, breaking, loading, hauling, and disposal add labor and equipment | Existing material, depth, access, hauling, and disposal fees |
| Excavation and support | Unsuitable soil, fill, elevation changes, and drainage work expand the preparation scope | Removal depth, subgrade work, aggregate material, compaction, and drainage |
| Access and placement | Restricted truck access may require pumping, buggies, extra labor, or smaller placements | Placement method, pump or equipment charges, and site protection |
| Edges and structural details | Thickened edges, footings, embedded items, and engineered details use more material and labor | Dimensions, reinforcement, inspections, and approved plans |
| Moisture control | Enclosed floors may need a vapor retarder, granular layer, penetrations, and flooring coordination | Material, seams, penetrations, location, and flooring requirements |
| Finish and protection | Texture, color, polishing, coatings, weather protection, and curing change materials and labor | Finish sample, curing method, weather plan, and return-to-service limits |
Use the project-specific cost guide when the slab is specialized
A generic slab rate becomes less useful when the project includes vehicle loads, decorative patio work, equipment requirements, or a structural foundation system. Use the closest project guide instead of forcing every slab into one range.
Equipment, shed, or hot-tub pad
Size examples and use-specific planning factors
Concrete patio
Patio pricing, finish options, access, and outdoor-living scope
Concrete driveway
Vehicle pavement, demolition, support, thickness, and finish
Slab foundation
Excavation, footings, structural details, moisture control, and engineering
How should you compare concrete slab quotes?
Compare one written scope rather than dividing every quote by square footage. A lower rate may exclude preparation, reinforcement, pumping, moisture control, curing, or cleanup that another contractor included.
- Slab dimensions, thickness, edges, footings, and elevations
- Demolition, excavation, subgrade work, aggregate base, drainage, and disposal
- Concrete strength and exposure requirements without treating PSI as the entire specification
- Reinforcement type, size or dosage, spacing, support, cover, and intended purpose
- Vapor retarder, penetrations, embedded items, joints, finish, and tolerances
- Placement access, pumping, weather protection, curing, cleanup, permits, and exclusions
Define those decisions in the concrete scope builder before checking a quote.
Already have a quote for your concrete slab?
Check it against regional averages — free, instant verdict.
Sources and limitations
Published consumer ranges use different definitions. Some describe a simple broom-finished slab, while others combine broader residential projects, preparation, reinforcement, or contractor-reported totals. Contractors for Concrete therefore uses $4 to $8 per square foot only as a basic four-inch starting range and routes specialized projects to narrower cost guides.
- HomeGuide 2026 contractor pricing guide: $4 to $8 for a basic slab
- HomeGuide 2026 consumer cost guide: $6 to $12 installed
- This Old House 2026 concrete slab cost guide
These are national planning references, not averages of contractor bids submitted to Contractors for Concrete. Local labor, concrete supply, minimum charges, access, preparation, design, and permit requirements can move a written quote outside the range. Last reviewed July 25, 2026.