Where is the water coming from?
Higher water bill, a warm spot on the floor, a puddle by the water heater, or a gurgling drain? Pick what you notice and answer a few follow-up questions. You'll get the likely source, how urgent it is, typical repair costs, and the article that explains it.
Slab leak repair: typical costs
This Old House puts the average at about $2,300, with a range of $630–$4,400 or more.
| Work | Typical range |
|---|---|
| Slab leak detection | $150–$600 |
| Broken pipe repair | $200–$2,000 |
| Water line repair | $300–$1,400 |
| Under-slab plumbing (access and repair) | $500–$4,000 |
| Rerouting plumbing | $1,500–$15,000 |
| Foundation repair after opening the slab | $2,000–$7,500 |
| Full slab replacement | $3,600–$8,000 |
Source: This Old House, Slab Leak Repair Cost (updated Apr 7, 2026; HomeAdvisor data).
When to call a licensed plumber
Water spreading across a floor, a warm spot on a slab floor, a leaking water heater, or sewage backing up into a drain needs a licensed plumber. Keep away from water near outlets or appliances, and shut off the water at the main valve only if you can reach it safely. If you smell gas near a gas water heater, leave the house and call your gas utility or 911 from outside. Never plug or cap a water heater's relief valve. Before anyone digs in your yard, call 811.