French drain cost: per foot, 50 to 150 feet, by state
Two sides, 100 ft of drain: about $2,950 to $3,850, typically $3,200. That's a French drain installed along the foundation, priced by the foot, plus the contractor's overhead, profit and sales tax. Everything in, it runs $29.75 to $38.25 a linear ft. A sump pump, a drain outlet at the street, cutting concrete and putting the yard back are extra.
Anthony Hicks30+ years in construction. Updated November 5, 2026.
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What it costs
| Job | Cost |
|---|---|
| One side of a house, 50 ft of drain | $1,600 to $2,150 |
| Two sides, 100 ft of drain | $2,950 to $3,850 |
| Most of a house, 150 ft of drain | $4,400 to $5,800 |
About $29.75 to $38.25 a linear ft, everything in.
Totals include the contractor's overhead and profit (20%) and the state's average sales tax. Prices as of November 2026.
What’s in these numbers
Each total is a typical job, priced the way a contractor’s estimate is priced:
| 50 ft | 100 ft | 150 ft | |
|---|---|---|---|
| Where | One side of the house | Two sides | Most of the house |
| Drain | A French drain along the foundation | Same | Same |
On top of the work:
- Overhead and profit: 20%, the standard markup on a contractor’s estimate.
- Sales tax on the materials, at the state’s average rate.
Not in them: a sump pump or a basin, an outlet at the curb or a dry well, cutting through a driveway or patio, waterproofing the wall itself, putting back the lawn and plantings, and permits.
What the code asks of a foundation drain
The residential code calls for drains around concrete or masonry foundations that hold back earth and enclose habitable or usable space below grade, unless the ground is well-drained soil such as gravel or sand (IRC R405.1). Where a drain goes in:
- It sits low: at or below the top of the footing, or below the bottom of the slab.
- It drains somewhere: by gravity or a pump into an approved drainage system.
- Gravel bed: perforated pipe or drain tile goes on at least 2 inches of washed gravel or crushed rock and is covered by at least 6 inches of it.
- Filter fabric: an approved filter membrane wraps the drain or covers the gravel, unless the drain’s maker says otherwise.
What moves the price
- Length. It’s priced by the foot, so each side of the house adds to it.
- Depth. A drain down at the footing means a deeper trench than one that catches surface water in the yard.
- Where the water goes. A long run to daylight or a pump to lift it adds pipe and equipment.
- What’s in the way. Concrete, decks, roots and utility lines slow the digging.
- Where you live. Pick your state in the box above.
Common questions
How much does a French drain cost per foot?
$29.75 to $38.25 a linear ft along the foundation, with overhead, profit and sales tax included.
How much is a 100 foot French drain?
About $2,950 to $3,850, typically $3,200.
How much for a short French drain?
About $1,600 to $2,150 for 50 feet along one side of a house.
Does a French drain need a sump pump?
Only where the water can’t run off by gravity. The code lets a foundation drain discharge by gravity or by mechanical means (IRC R405.1); the sump pump cost guide prices the pump.