Basement leak repair: $250 to $5,000, where water gets in

Basement leak repair cost

National figures. HomeGuide's minor range is crack sealing and small drainage fixes; its major range is a drainage system or exterior waterproofing.

Foundation leak repair costs $250 to $5,000 or more for minor work and $4,500 to $15,000 or more for major work in HomeGuide's February 2026 guide; Angi's August 2026 figure for foundation leaks is $2,000 to $7,000 and This Old House's is $2,300 to $7,300. The low end is a single crack injection at $250 to $800; the high end is an interior drain and sump at $4,000 to $17,000 or exterior waterproofing at $10,000 to $15,000 or more (HomeGuide). Where the water comes in decides which one you are paying for.

Do this now: find where the water gets in

1. Power and photos. Do not touch electrical equipment if it is wet or you are standing in water (Red Cross). Photograph the water and the damage before you clean up. If a pipe burst, call your insurer before any contractor; seepage is treated as maintenance and generally not covered (Maryland Insurance Administration). Never sign a claim over to a contractor.
2. Watch it during a rain. Water at the floor-wall joint or coming up through a floor crack means water under the slab; a wet streak down a wall crack, a wet window well or a drip at a pipe means the wall. Mark the spots.
3. Rule out condensation and plumbing. UMN Extension says summer condensation on cool walls is often mistaken for leakage; a plastic square taped to the wall separates the two. A leak in dry weather is plumbing; see leak detection.
4. Walk the outside at that spot. Downspouts should discharge at least 4 feet out and the grade fall 1 inch per foot for 6 feet (UMN Extension). HomeGuide prices downspout work at $220 to $625 and regrading at $1,000 to $5,000, the cheapest lines on the page.
5. Dry within 24 to 48 hours. EPA's window for preventing mold. Wet carpet and drywall that stay wet become a mold remediation job at $1,500 to $15,000 (HomeGuide).

Is it an emergency? Seepage vs flooding

A damp line along the floor after a storm is seepage and can wait for a dry week. Water rising across the floor, a sump pump that has stopped with water at the pit rim, or water with wiring or a furnace in it is flooding: see basement flooding for the first hour and sump pump repair for the pump. Water coming through a horizontal crack in a wall that is bowing is the one leak that is also a structural problem; the bowing basement walls guide covers it.

Where basement water comes in, and what each fix costs

Wall cracks

A leaking hairline, vertical or diagonal crack in poured concrete is sealed by epoxy or polyurethane injection for $250 to $800 or more per crack (HomeGuide). This Old House says injection seals narrow cracks and keeps water out but does not address movement, which is why a horizontal or stair-step crack is priced at $1,000 to $5,000 minor and $10,000 to $30,000 major instead: the crack is a symptom of the wall or footing moving. Basement crack repair explains how to tell them apart. HomeGuide says water also enters through gaps around pipes and deteriorating mortar joints, and that block walls leak more than poured concrete.

The floor-wall joint and floor cracks

Water seeping where the floor meets the wall, or up through floor cracks, is groundwater under the slab, and no wall coating fixes it. The repair is an interior drain tile along the slab edge with a sump: $4,000 to $17,000 (HomeGuide) or $5,000 to $18,000 (Angi), at $40 to $85 per linear foot. UMN Extension calls the beneath-slab interior system the most effective interior option and says above-slab channels cannot drain groundwater under the slab. Basement waterproofing cost compares interior and exterior systems.

Window wells

A window well that fills in a storm leaks at the sill. UMN Extension says wells should be filled from the footing to the sill with 3/8- to 3/4-inch coarse aggregate so water drains to the footing drain; a well that sits on undrained soil or has a clogged drain is a bucket against the house. A cover and a cleared drain are the first fix; the exterior drain at $30 to $90 per linear foot (HomeGuide) is the second.

Pipe penetrations and the top of the wall

Water at a pipe or conduit where it passes through the wall is a sealing job, usually priced with crack injection. Water running down the inside of the wall from the top is a grading, gutter or siding problem, not a foundation one; the roof puts about 1,250 gallons on the ground per inch of rain on a 2,000-square-foot house (UMN Extension).

Interior drain and sump vs exterior membrane

Interior waterproofing costs $4,500 to $10,000 or more and exterior $10,000 to $15,000 or more in HomeGuide's leak guide. The interior system lets water in and pumps it out; the exterior membrane and drain keep the wall dry. UMN Extension ranks exterior drainage as "the most costly but most effective option" and says interior coatings are temporary and "generally won't solve the problem in the long term" without drainage. For a leak that follows heavy rain and appears at the floor edge, the interior drain is the usual answer; for a wall that stays wet, a block wall, or a finished basement you do not want torn out, exterior work gets quoted.

Basement leaking after heavy rain: the outside fixes

Grading, downspouts and yard drains are where UMN Extension starts and where the money is smallest: $220 to $625 for downspouts, $1,000 to $5,000 for regrading, $500 to $8,800 for an exterior French drain (HomeGuide). The EPA's mold guide says to make sure the ground slopes away from the foundation. French drain cost prices the yard drains, curtain drains and dry wells that carry roof water away.

Insurance and licensing

Standard homeowners policies exclude flood, earthquake, landslide and sinkhole damage and damage from lack of maintenance (Triple-I), and the Maryland Insurance Administration says water that seeps in through a foundation wall or floor is treated as a maintenance issue and generally not covered. A burst pipe is the usual exception. Does homeowners insurance cover home repairs covers the lines.

Texas has no state license for foundation repair: a 2011 bill that would have created one (S.B. 1399) said at the time that "there is no state regulation in place to directly mitigate these risks," and the Texas Department of Licensing and Regulation's list of 41 regulated industries still has no foundation repair program. Other states differ, so check your own state's contractor board, ask for the license number if your state issues one, and ask for proof of insurance either way. Basement waterproofing pages: Chicago, Columbus, Indianapolis, St. Louis, Pittsburgh, Philadelphia, Minneapolis. Calls go to an independent company that serves your area and takes this kind of job; hours vary. How calls work.