2026 cost reference
Drain location changes the economics
A shallow trench in an open yard is much easier to install than an interior system that requires cutting a basement slab or a deep exterior system that requires excavation alongside the foundation.
Length alone is not enough
Depth, soil, access, disposal, gravel, pipe, landscape restoration and the outlet location can all change a bid. Ask for the measured length and system type before comparing totals.
Do not confuse drainage with a complete waterproofing scope
A French drain manages water movement. A broader basement or foundation-waterproofing proposal may also include sump equipment, wall treatment, crack work, grading or finish restoration.
Frequently asked questions
How much does a French drain cost per foot?
HomeGuide's 2026 data places shallow yard drains around $10–$35 per linear foot, interior basement systems around $40–$85 per foot, and deep exterior footing drains around $30–$90 per foot.
Why does an interior basement French drain cost more?
Interior systems usually require cutting and restoring concrete, installing drainage beside the footing and connecting the system to a sump or discharge path.
Can I compare two French-drain quotes by total price alone?
Only if the drain type, length, depth, outlet, restoration work and included equipment are comparable. Otherwise the totals may represent different scopes.
The calculator uses the same reviewed source ranges shown on this page.
Related cost guides
These figures may be quoted with attribution and a link. Source-check date: October 2, 2026.