Point-of-sale septic inspections in Snohomish County
Starting November 1, 2026, every property sale in Snohomish County on a septic system needs an inspection and a Report of Property Transfer before it closes. That is new. The county adopted ordinance BOH26-02 in April 2026, and it covers roughly 84,000 septic systems, with about 2,785 septic properties changing hands in a typical year. If you are selling a home in Stanwood, Warm Beach, Lake Goodwin, or anywhere else in the county, here is exactly what the rule requires and the order to do it in.
Short version: it is five steps, it costs most sellers $545 to $845 all-in, and none of it is hard if you start when you list instead of when you get an offer.
What BOH26-02 actually requires
Strip out the code language and the ordinance asks for four things at sale. It applies to residential, commercial, and duplex properties alike, any sale where the property has an on-site septic system.
- An inspection by a Health District-certified septic professional, completed within 12 months of closing.
- The tank pumped, but only if the inspector recommends it. No automatic pumping requirement.
- An as-built record of your system on file with the county. If yours is missing, a certified contractor draws a site plan to replace it.
- A Report of Property Transfer (RPT) filed with the Snohomish Health Department, with a $245 fee for 2026-27.
One exemption: systems installed within the past 12 months skip the inspection, because they already passed the county's final inspection at install. Everything older goes through the process.
The seller timeline, step by step
Do these in order and the septic side of your sale runs quietly in the background while your agent does the rest.
1. Pull your septic records
Start with the Health Department's file on your system: the as-built drawing, permits, and any past inspection reports. This tells you what kind of system you have, where the tank and drainfield sit, and whether your as-built is on file. If the as-built is missing, you know now instead of at step four. We pull records for sellers as part of the package, no charge to look.
2. Get the inspection
A Health District-certified septic professional inspects the system: tank condition, baffles, sludge and scum levels, the drainfield, and any pumps or alarms. Expect 1 to 2 hours on site and $300 to $600 depending on system type and access. Gravity systems run cheaper to inspect than pressure or ATU systems because there is less equipment to check.
3. Pump the tank if the inspector recommends it
Pumping is not automatic. BOH26-02 requires it only when the inspector recommends it, usually because sludge and scum have built up past the working limit. If it is flagged, pumping runs $400 to $700, and the smart move is doing it the same visit as the inspection so you pay one trip charge instead of two. See our pumping page for what drives that price.
4. Get a site plan drawn if your as-built is missing
The county requires an as-built record on file. Plenty of older systems around Cedarhome and East Stanwood predate good recordkeeping, so missing as-builts are common, not a scandal. The fix is a certified contractor locating the components and drawing a site plan. Handle it in the same window as the inspection and it does not add days to your timeline.
5. File the Report of Property Transfer
The RPT goes to the Snohomish Health Department with the $245 fee (2026-27 rate; it rises to $255 the following year). The county takes up to 10 business days to review it. Once accepted, it is valid for 12 months. File at listing and the review window costs you nothing. File after mutual acceptance and those 10 days sit right on top of your closing date.
What it costs, line by line
Three numbers cover almost every sale, and each range has a reason.
- RPT fee: $245 for the 2026-27 year, set by the county. It rises to $255 for 2027-28, so filing this year is slightly cheaper than next.
- Inspection: $300 to $600. System type and access move the price more than anything. A gravity system with an easy-to-find tank sits at the low end; pressure and ATU systems with pumps and control panels to test sit higher.
- Pumping, if recommended: $400 to $700. Tank size and access drive it. This is a conditional cost; if your sludge levels are fine, you do not pay it.
For a fuller breakdown of what moves each number, see our septic inspection cost guide.
The 12-month rule, twice
Twelve months shows up in two places in this ordinance, and they work in your favor.
First, the inspection must be within 12 months of closing, and an accepted RPT is valid for 12 months. That means an inspection ordered at listing does not go stale during a normal sale, and if a deal falls through you can usually relist without repeating the work.
Second, systems installed within the past 12 months are exempt entirely. If you replaced your system last spring, your permit and final inspection paperwork stand in for the point-of-sale inspection. Keep those documents handy for the buyer regardless.
If the inspection finds a deficiency
This is the part sellers worry about, so here is the straight answer. A deficiency does not kill your sale. It gives you a decision.
Option one: repair before closing. A cracked baffle or a failed pump is a bounded, quotable fix. You repair it, the paperwork shows a clean system, and the negotiation never happens.
Option two: let it transfer to the buyer. Under Chapter 5.55 of the Board of Health code, unresolved deficiencies transfer with the property. That is legal, but it turns the deficiency into negotiation material. The buyer knows the repair is now theirs, so expect a price concession or a repair demand roughly sized to the fix.
The math usually favors fixing small problems early. A drainfield in real trouble is a different conversation, because replacement runs $10,000 to $30,000 or more; our drainfield repair page covers the warning signs and options. Either way, finding out at listing beats finding out a week before closing.
One call instead of five
The Sell-Ready Septic Package
Every step above is a separate phone call if you do it yourself: records office, inspector, pumper, contractor for the site plan, county filing. We bundle all of it. One call gets you the records pull, the inspection by a Health District-certified septic professional, pumping if and only if it is flagged, a site plan if your as-built is missing, and the Report of Property Transfer filed with the county. You get one date on the calendar and paperwork that is done before your buyer ever asks about it.
Real estate agents: we built a resource page for you too, with the transaction timeline your clients will ask about. See our agent page.
Not selling yet? Stay ahead of the rule
The cheapest point-of-sale inspection is the one your system was already ready for. Snohomish County's routine guidance: gravity systems get inspected every 3 years, pressure, ATU, and other alternative systems every year, and new systems get 6-month checks for their first 2 years. A system on that schedule walks into a point-of-sale inspection with no surprises, because someone qualified looked at it recently.
Routine care also builds the paper trail a buyer wants to see, and the county's Savvy Septic program offers rebates that take some of the sting out of maintenance costs. Pumping every 3 to 5 years remains the cheapest insurance there is against a $10,000-plus drainfield failure; our pumping page covers what that costs and why.
Selling on Camano? Different county, different rules
Camano Island is Island County, which has its own time-of-sale inspection requirement with its own inspector licensing and validity windows. Do not assume the Snohomish process applies over the bridge. Our Camano Island septic inspection guide walks through Island County's process.
And a note for the rest of the state: Washington is heading the same direction as Snohomish County. WAC 246-272A-0270 makes point-of-sale septic inspections mandatory statewide on February 1, 2027. If you are selling elsewhere in Washington, our statewide seller's guide compares the rules county by county.
Common questions
Do I need a septic inspection to sell my house in Snohomish County?
Yes, starting November 1, 2026. Ordinance BOH26-02 requires an inspection by a Health District-certified septic professional within 12 months of closing for every property sale on a septic system, residential or commercial. You also file a Report of Property Transfer with the Health Department and pay a $245 fee. The only exemption is a system installed within the past 12 months.
What is a Report of Property Transfer (RPT)?
The RPT is the paperwork Snohomish County requires when a septic property changes hands. It packages the inspection results and your system records and goes to the Health Department with a $245 fee for 2026-27 ($255 the following year). The county takes up to 10 business days to review it, and once accepted it stays valid for 12 months.
How much does the whole point-of-sale process cost?
Plan on $545 to $845 for most sales in Snohomish County: $300 to $600 for the inspection and $245 for the county RPT fee. If the inspector recommends pumping, add $400 to $700. If your as-built record is missing, a certified contractor has to draw a site plan, which adds a separate charge. System type and access drive most of the variation.
How long does the inspection and filing take?
The inspection itself usually takes 1 to 2 hours on site. The county's review of the Report of Property Transfer takes up to 10 business days after filing. That is why we tell sellers to order the inspection when the home is listed, not after mutual acceptance. Done early, the paperwork is finished before it can hold anything up.
How long is the inspection good for?
The inspection must be within 12 months of closing, and an accepted Report of Property Transfer is valid for 12 months. So an inspection done at listing covers you through a normal sale timeline with plenty of room. If a sale falls through and you relist within the year, you usually do not need to start over.
What if the inspection finds a problem?
You have two paths. Repair the deficiency before closing, or disclose it and let it transfer to the buyer, because under Chapter 5.55 of the Board of Health code unresolved deficiencies follow the property. In practice that makes any deficiency negotiation material: buyers ask for a repair or a price concession. Small fixes handled early cost far less than concessions negotiated under deadline pressure.
Is my system exempt if it was recently installed?
Only if it was installed within the past 12 months. A brand-new system already went through county permitting and final inspection, so BOH26-02 does not make you inspect it again at sale. Anything older than 12 months needs the point-of-sale inspection, even if it has been trouble-free.
Does this rule apply on Camano Island too?
No. Camano Island is Island County, which has required a time-of-sale septic inspection since 2008 under its own rules: the inspector must be an Island County Licensed Maintenance Service Provider, and validity runs 12 months for alternative systems or 3 years for conventional ones. Different county, different paperwork. See our Camano Island page for that process.
Talk to a septic pro today
One call handles it: inspection, pumping if it's needed, and the county paperwork done right the first time.
Call (360) 454-9079