What does a septic inspection actually cost in Snohomish County?
Updated for the point-of-sale rule effective November 1, 2026.
There are two separate costs people mix up: the county's application/report fee, and the inspector's own service charge for actually coming out, evaluating the system, and pumping the tank if it needs it. Both apply. Here's the realistic breakdown.
The county fee
| Period | Fee |
|---|---|
| 2026–2027 | $245 |
| 2027–2028 | $255 |
This covers the county's review of the inspection application and report — it isn't the inspector's fee.
The inspector's service fee
A typical certified septic inspection in the Puget Sound region runs in the neighborhood of $300–$500 for a straightforward single-family system, before any pumping. If the tank needs pumping as part of the inspection — common if it hasn't been serviced in a few years — add roughly $400–$700 depending on tank size and access. Larger or more complex systems (mound systems, sand filters, pressure-dosed systems) generally cost more to evaluate than a standard gravity system.
| Item | Typical range |
|---|---|
| County application/report fee | $245–$255 |
| Inspector's evaluation fee | $300–$500 |
| Tank pumping (if needed) | $400–$700 |
| Minor repair (baffle, riser, lid) | $300–$1,500 |
| Drainfield or major component repair | $3,000–$15,000 |
| Full system replacement | $15,000–$35,000+ |
Ranges reflect general Puget Sound-area septic service pricing and are not quotes. Soil type, system type, site access, and permitting all move these numbers — get an actual quote from a certified local inspector for your property.
Who pays for the inspection?
The county rule doesn't dictate who pays — that's a negotiation between buyer and seller, same as any other pre-sale inspection. In practice, it's almost always the seller who pays for the point-of-sale inspection itself, since it's their obligation under the new rule. What happens if the system fails is a separate, more complicated question — see who pays when a septic system doesn't pass.
Budgeting tip
If your system hasn't been pumped in the last 2–3 years, budget for pumping as part of the inspection rather than treating it as a surprise add-on — most inspectors will need an empty or near-empty tank to properly evaluate it anyway.