Basement Bathroom Addition Cost Calculator
Estimate the cost of adding a bathroom to your basement based on bathroom type, plumbing approach, and fixture quality.
Last updated: March 25, 2026
Basement Bathroom Addition Cost Calculator
Estimate the cost of adding a bathroom to your basement based on bathroom type, plumbing approach, and fixture quality.
Estimated Total
$14,325
Itemized Breakdown
This calculator provides estimates based on national averages adjusted for your region. Actual costs may vary significantly based on specific project conditions, contractor availability, material prices, and local market factors. Always get at least 3 quotes from licensed, insured contractors before starting your project.
Want the full picture?
Read our complete Basement Bathroom Addition cost guide with material comparisons, contractor tips, savings strategies, and regional pricing data.
Quick Cost Reference
Cost by Tier
Half bath (toilet and sink) added to unfinished basement near existing stack. Basic fixtures, standard tile, and minimal framing.
Full 3-piece bath (toilet, sink, shower) with below-slab ejector or macerating toilet system, mid-range tile, standard vanity, and proper ventilation.
Full bath with tile shower, premium fixtures, custom vanity, below-slab plumbing with ejector pump, heated floor, and full exhaust ventilation system.