Concrete Foundation Cost
A slab-on-grade foundation costs $4 to $12 per square foot, a crawlspace $10 to $18, and a basement $20 to $50 (Fixr, February 2026). For a 1,500 sq ft footprint, that's roughly $6,000 to $75,000 depending on the type.
On this page
Foundation cost per square foot
Per square foot of footprint:
| Foundation | Fixr, Feb 2026 [1] | HomeGuide [2] |
|---|---|---|
| Slab-on-grade | $4–$12 | $4–$8 |
| Crawlspace | $10–$18 | $8–$18 |
| Basement | $20–$50 | $35–$50 |
Fixr describes slab-on-grade as the most affordable option because it needs minimal excavation, while crawlspaces need a shallow dig and basements the most. HomeGuide’s basement figure excludes interior finishing.
Cost by footprint
At Fixr’s ranges:
| Footprint | Slab-on-grade | Crawlspace | Basement |
|---|---|---|---|
| 1,000 sq ft | $4,000–$12,000 | $10,000–$18,000 | $20,000–$50,000 |
| 1,500 sq ft | $6,000–$18,000 | $15,000–$27,000 | $30,000–$75,000 |
| 2,000 sq ft | $8,000–$24,000 | $20,000–$36,000 | $40,000–$100,000 |
HomeGuide puts a typical unfinished basement foundation at $52,000–$100,000 [2].
Block or poured walls
Crawlspace and basement walls are either poured concrete or concrete block. Homewyse puts an installed concrete block wall at $15.11–$19.61 per square foot of wall (May 2026) [3]. Use the block calculator to count blocks for a wall, and the footing calculator for the footing under it.
Not a design tool
Foundation type, depth, reinforcement and footing size are engineering and code decisions. These figures help you check whether a builder’s number is in the right range. They don’t replace a site-specific design.
Frequently asked questions
What is the cheapest type of foundation?
Slab-on-grade. Fixr puts it at $4–$12 per sq ft and calls it the most affordable option because it needs minimal excavation. HomeGuide gives $4–$8.
How much does a basement foundation cost?
Fixr gives $20–$50 per sq ft and HomeGuide $35–$50, before interior finishing. HomeGuide says most homeowners spend $52,000–$100,000 on an unfinished basement foundation.
Can I use these prices to budget a new house?
As a first check only. Foundation design depends on soil, frost depth, loads and local code, and is set by an engineer or builder. Get a quote based on your plans.
Sources
- Fixr, Concrete foundation cost, updated 2026-02-13. Checked September 23, 2026.
- HomeGuide, Foundation cost. Figure as shown in the page's search listing; checked September 23, 2026.
- Homewyse, Cost to install a concrete block wall, updated 2026-05. Checked September 23, 2026.