Foundation repair cost calculator
HOW MUCH DOES FOUNDATION REPAIR COST?
HomeGuide puts foundation repair at $250 to $800 per crack for minor cracks, $2,000 to $12,000 for leaks and $4,500 to $20,000 for settling, sinking or bowed walls. In Seattle, Angi lists a typical range of $2,625 to $10,466, with an average of $6,455. Pick your problem below to see the range for it.
How the calculator works
- Problem. Each problem has a published price range from HomeGuide (U.S.) and Angi (Seattle). We show both, because the two guides don't agree.
- Cracks. HomeGuide's $250–$800 is per crack, so it's multiplied by the number of cracks. Angi's Seattle range of $700–$4,000 is for the job, so it isn't multiplied.
- Sunken slab. HomeGuide gives $4–$9 per square foot for slab jacking (mudjacking), so it's multiplied by the area. Angi's Seattle range of $1,500–$4,000 is for the job.
- Extras. An engineer report or inspection is added if you tick it. Sales tax is added at Seattle's 10.55% rate if you tick the box, because Washington contractors collect sales tax on the whole contract, labor included (Department of Revenue).
Rates used
| Problem | Seattle (Angi) | U.S. (HomeGuide) | Common fixes (HomeGuide) |
|---|---|---|---|
| Cracks | $700–$4,000 | $250–$800 per crack | Epoxy or crack stitching |
| Leaks | $2,100–$10,200 | $2,000–$12,000 | Crack sealing, drainage, waterproofing |
| Settling or sinking | $10,000–$35,000 | $4,500–$20,000 | Mudjacking, piering, helical piers |
| Bowed walls | $6,500–$13,000 | $5,000–$15,000 | Wall anchors, carbon fiber straps, helical tiebacks |
| Sunken slab | $1,500–$4,000 | $4–$9 per sq ft | Slab jacking (mudjacking) |
Other foundation work
| Work | Seattle (Angi) | U.S. (HomeGuide) |
|---|---|---|
| Piering or underpinning | $2,500–$9,900 | $10,000–$20,000 |
| Stabilization or reinforcement | $7,500–$18,000 | $5,000–$10,000 |
| Interior waterproofing | $2,000–$10,000 | $4,500–$15,000 (basement) |
| House lifting | $30,000–$50,000 | $10,000–$40,000 |
| Lifting and replacing the foundation | not listed | $20,000–$100,000 |
Angi says Seattle foundation pros who charge by the hour generally charge $235 to $300 per hour, and that most repairs run $1.50 to $12 per square foot.
Do you need a permit in Seattle?
- SDCI says you need a permit for any work on load-bearing supports, "no matter how small the project." A foundation is load-bearing.
- Angi's Seattle page says underpinning, lifting and other work that restores structural integrity needs an SDCI permit, while minor non-structural repairs may not.
- Not sure? Call SDCI at (206) 684-8600 before work starts.
Bolting the house to its foundation for earthquakes is a separate job with its own City permit. See seismic retrofit cost in Seattle. A wet basement without structural damage: basement waterproofing cost in Seattle.
Before you sign
- For settling, sinking or bowed walls, HomeGuide says a structural engineer report ($500–$3,000) helps determine the best repair method. An engineer doesn't sell the repair, so the report is a neutral second opinion.
- Get the same repair method, number of piers or anchors, and warranty in writing from every contractor.
- Look the contractor up on L&I's Verify a Contractor tool. For jobs of $1,000 or more on a home, the contractor must give you a written disclosure statement before work starts (RCW 18.27.114).
Frequently asked questions
How much does foundation repair cost?
HomeGuide puts it at $250 to $800 per minor crack, $2,000 to $12,000 for leaks and $4,500 to $20,000 for settling, sinking or bowed walls. In Seattle, Angi lists $2,625 to $10,466, with an average of $6,455. Seattle's 10.55% sales tax applies to the whole contract.
How much does it cost to fix a crack in a foundation?
HomeGuide lists $250 to $800 per crack for epoxy or crack stitching. Angi lists $700 to $4,000 for crack repair in Seattle.
How much does it cost to fix a sinking foundation?
HomeGuide lists $4,500 to $20,000, depending on the house size, foundation depth and repair method. Angi lists $10,000 to $35,000 for differential settlement in Seattle.
Do I need a structural engineer for foundation repair?
For small cracks, often not. For settling, sinking or bowed walls, HomeGuide says an engineer report, at $500 to $3,000, helps determine the best repair method.
Why doesn't the calculator ask for my address or phone number?
It doesn't need them. The math runs in your browser, and nothing you enter is sent anywhere or stored.
Sources
- HomeGuide — How Much Does Foundation Repair Cost? (February 6, 2026)
- Angi — Foundation repair cost in Seattle, WA (updated Oct 8, 2025)
- Seattle SDCI — Do You Need a Permit?
- Washington Department of Revenue — Custom construction; Seattle rate change, January 1, 2026
- RCW 18.27.114 and L&I — Hiring a contractor
All sources accessed October 14, 2026. Angi's Seattle page uses an older 10.40% sales tax rate.
This calculator gives a rough range from published average rates. It is not a quote, and it can't diagnose your foundation. Foundation problems can be structural; have a licensed contractor or structural engineer inspect before deciding. Nothing you enter is sent anywhere or stored. See our disclosure and disclaimer.