Cost to Bathroom Plumbing Rough-In in Seattle, WA (2026)

If you’re budgeting a bathroom plumbing rough-in in Seattle, most projects run $3,142-$10,054, 26% above the $4,500 national average. What moves that number most is usually one thing: Distance from Main Stack. On its own it can swing the cost by $1,000 - $5,000, so that’s the decision to slow down on before you sweat the smaller stuff.

Easiest place to save: Position the new bathroom as close to the main drain stack as possible - every 10 feet of additional drain run adds $300-$600 in materials and labor

In the West Coast (where Seattle sits): CA licensed plumbers command 25-35% premium over national average; permit processing can be slow.

$3,142-$10,054 in Seattle

26% above the national average · 1.26x cost multiplier

In Seattle, a bathroom plumbing rough-in runs $3,142 to $10,054 on average - about 26% above what homeowners pay nationwide. The West Coast market's labor costs account for most of the gap, with material pricing and local permitting fees adding to the spread. Use the cost table below to compare budget, mid-range, and premium options side by side.

Cost Breakdown in Seattle

Line ItemLowMidHigh
Cost per fixture$628$1508$3142
Materials$912$1,710$3,420
Labor$2,667$4,667$9,334
Permits$684$912$1,710
Total$4,263+25% vs. national avg$7,289+26% vs. national avg$14,464+26% vs. national avg

Budget

Single bathroom, close to existing stack, supply and drain.

Mid-Range

Full bathroom rough-in, moderate distance from stack, proper venting.

Premium

Remote location, slab penetration or long run, complex venting.

Material Options

Material prices below are national averages; availability in Seattle may shift costs slightly.

MaterialCost/UnitBest For
PEX Supply Lines$0.50-$1.50/ftMost residential supply line applications; the dominant choice in new constructionFlexible, freeze-resistant, fast to install, less expensive than copper
Copper Supply Lines$2-$4/ftHomes with existing copper systems where matching is requiredLong-lasting, naturally antimicrobial, handles high heat
ABS Drain Pipe$1-$2/ftNew construction and additions in areas where it's code-approvedLightweight, easy to cut and glue, lower cost than cast iron
PVC Drain Pipe$0.80-$1.50/ftStandard drain and vent applications in most residential projectsWidely code-approved, durable, resistant to chemicals
Cast Iron Drain$3-$8/ftMatching existing cast iron systems in older homesVery quiet, extremely durable, required in some jurisdictions

Other Projects in Seattle

Seattle Estimate

Typical Range

$3,142-$10,054

vs. National Average

26% above national

Cost Multiplier

1.26x

Cost Per fixture

$628-$3142

This 1.26x estimate prices Seattle labor from BLS Occupational Employment and Wage Statistics (May 2025) and applies a lighter regional adjustment to materials and permits, which vary less by metro than labor does. Actual bids vary by contractor, project scope, and timing.

See national average costs →