How much does it cost to replace a sewer line in Seattle, WA?
Full sewer line replacement in Seattle, WA typically runs $4,000–$12,000 depending on length, depth, and what's above it — driveways and landscaping raise the price. A spot repair of one bad section runs $1,500–$4,000. Trenchless methods (pipe lining or bursting) often land in the same range but spare your yard; they only work if the old line hasn't collapsed.
Likely causes
- Tree root intrusion — Roots find the joints in clay and cast-iron lines — the #1 reason older lines fail.
- Collapsed or bellied pipe — A sagging section ('belly') collects waste until the line backs up chronically.
- End-of-life pipe material — Homes from the 1940s–70s may have fiber (Orangeburg) pipe that deforms and fails wholesale.
What you can check yourself
- Get a camera inspection and keep the video file — never approve a replacement from a verbal description alone.
- Ask for spot-repair vs full-replacement pricing in writing; one bad joint doesn't always condemn the line.
- Check whether your city has a sewer lateral program or your insurance has a service-line rider — many homeowners hold $10k+ of coverage they don't know about.
- Get two quotes: excavation pricing varies enormously with depth and access.
Typical cost
Typical in Seattle, WA: camera inspection $250–$500; spot repair $1,500–$4,000; full replacement $4,000–$12,000; trenchless lining $80–$250 per foot.
When to call a pro
Sewage backing up into the lowest drain, multiple fixtures draining slowly at once, or a lush sunken strip over the line in the yard — have it scoped this week, not this season.
Plumber pros in Seattle, WA
- National Pump Supply · 1700 7th Ave Ste 2100, Seattle, WA · +12064531956
- A Toms Sewer and Drain LLC · PO BOX 88563, SEATTLE, WA · 2066505135
- Seattle Service Plumber · 815 1st Ave, Seattle, WA · +12064295540
- Royal Rooter Home Services LLC · 85 S Washington St Ste 316, Seattle, WA · +12065957003
- Beacon Plumbing - Seattle · 515 7th Ave S, Seattle, WA · 2067202040
- BEACON PLUMBING & MECHANICAL INC · 515 7TH AVE S, SEATTLE, WA · 2538540182
- Paradiso Mechanical LLC · 2609 2nd Ave, Seattle, WA · +12062516854
- US Plumbers Home Service Seattle · 2001 3rd Ave, Seattle, WA · (206) 338-0659
Get free quotes from Seattle, WA pros →
Data by Servik — verified local pros from official license records and public sources. Cost figures are typical ranges, not quotes; a pro's written estimate is the real number.