From 1 February 2027 this becomes a statewide requirement: every property transfer will need an inspection by an inspector the local health officer has authorised.
Septic Rules When a Washington Home Sells
Local rules apply- Who May Inspect
- Routine inspections must be done by a maintenance service provider authorized by the local health officer. The property transfer inspection beginning February 1, 2027 must be done by a third-party inspector authorized by the local health officer under WAC 246-272A-0260(5). Counties such as Island and Thurston require their own certified or licensed providers.
- Report Rules
- No single state form yet; counties set submittal rules. Thurston requires a Time of Transfer application with the pumper's sketch and fee, inspected within the prior 12 months; Spokane requires a reviewed report, valid 12 months, filed before closing. Sellers must also give buyers maintenance records and the RCW 64.06 disclosure.
- County Programs
- The 12 Puget Sound jurisdictions under ESHB 1458 are Clallam, Island, Jefferson, Kitsap, Mason, San Juan, Skagit, Snohomish, Thurston, Whatcom, Seattle-King and Tacoma-Pierce. Island County has required transfer inspections since 2008; Thurston runs a Time of Transfer program and Spokane a Property Transfer Inspection program. In Marine Recovery Areas, pumpers and inspectors must report failing systems to the health jurisdiction.
- Advanced Systems
- WAC 246-272A-0270(1)(e) requires annual inspection of every system other than a septic tank with gravity drainfield, which covers mounds, pressure distribution systems, sand filters and aerobic treatment units. Proprietary treatment products must be inspected per the manufacturer's recommendations, and local health officers may require more frequent service.
- Pump-Out Rules
- No statewide pump-out interval; tanks are pumped when the inspection shows it is needed. Counties enforce this at transfer: Spokane requires pumping if the transfer inspection recommends it, and Thurston requires pumping within the 12 months before the application.
Set and enforced by Washington State Department of Health (DOH), Wastewater Management Program. Confirm the rule for a specific property with them or the county health office.
Private Well Rules When a Washington Home Sells
Local rules applyThere is no statewide well inspection or water test requirement at transfer. Kitsap County does require a Health District Water Status Report before sale for properties on a private one- or two-party source or a Group B system, and several Puget Sound counties require water adequacy review for building permits.
- Who May Test
- Varies locally. Kitsap Public Health District prepares the Water Status Report; Snohomish County Health Department reviews but does not inspect existing wells, so the owner hires a well inspection company. Samples are analyzed by a state-certified drinking water lab. Well construction and decommissioning require a licensed driller.
- What Is Tested
- Washington DOH and Ecology recommend coliform bacteria (zero present), nitrate (10.0 mg/L) and arsenic (0.010 mg/L) as the routine panel. For an existing well serving a new or accessory dwelling, Snohomish County requires a documented yield of at least 400 gallons per day per residential connection.
- Disclosure at Sale
- Washington's seller disclosure statement (RCW 64.06.020, 'Form 17') requires the seller to identify the water source, including a private well, and answer whether it provided an adequate year-round supply of potable water, plus problems, system defects, easements, treatment and water rights.
- Unused Wells
- An abandoned well must be decommissioned by a licensed well driller under WAC 173-160-381; owners may not do it themselves. The owner files a notice of intent 72 hours ahead and pays a $50 fee, and may be liable for resulting contamination. Transfer is not a state trigger.
- Distance From Septic
- WAC 173-160-171(3)(b) requires a non-public well to be at least 50 ft from a septic tank, holding tank, pump chamber or distribution box, 100 ft from the edge of an existing, proposed or reserve drainfield, and 50 ft from building, public or non-perforated sewer lines.
Set and enforced by Washington State Department of Ecology - Water Well Construction and Licensing Program (well construction and decommissioning); Department of Health and local health jurisdictions for water quality. Confirm the rule for a specific property with them or the county health office.
County and Town Rules in Washington
8 localities ask for something extra when a property changes hands. Everywhere else in the state, the state rules above are the whole answer.
Clallam CountySeptic
Since 1 June 2010 a Clallam County seller must give the buyer a current septic System Status Report at property transfer.
- What Is Required
- A professional System Status Report prepared by a licensed septic system designer or licensed OSS maintenance provider on file with Environmental Health, plus any available maintenance records, handed to the buyer.
- When
- The report must have been performed within 12 months of the property transfer, so it is effectively current for 12 months.
- Filed With
- The report goes to the buyer; reports for governmental actions are submitted to the county and recorded in the parcel file within 30 days.
Confirm with the locality before you rely on it: Clallam County source page.
Island CountySeptic
Island County has required a septic inspection before closing on any property served by an on-site septic system since 2008.
- What Is Required
- A septic inspection performed by an Island County licensed Maintenance Service Provider, resulting in an Island County Public Health On-Site Sewage Inspection Report the buyer may review.
- When
- Before closing. An inspection within the past year counts for alternative systems; within the past three years for conventional gravity or pressure systems.
- Filed With
- Island County Public Health; reports are posted to OnlineRME and the buyer gets a copy.
Confirm with the locality before you rely on it: Island County source page.
King County (Seattle & King County)Septic
A King County septic property must be inspected by a certified maintainer and have the operation and maintenance notice recorded on title before title transfers.
- What Is Required
- Inspection by a certified on-site system maintainer, and recording of the Notice of On-site Sewage System Operation and Maintenance Requirements with the King County Recorder if not already on title. Limited waivers exist.
- When
- Before transfer of title. Public Health reviews the report within 10 business days. A waiver based on a recent monitoring report needs that report to be under 6 months old.
- Filed With
- The maintainer submits the report to Public Health - Seattle & King County; the buyer pays the O&M program fee at transfer.
Confirm with the locality before you rely on it: King County (Seattle & King County) source page.
Kitsap CountySeptic and well
Kitsap Public Health District must prepare a Property Conveyance Inspection for septic properties and a Water Status Report for private-well properties before the sale.
- What Is Required
- Septic: a Property Conveyance Inspection (records review plus site inspection) by the Health District, required by Kitsap Public Health Board Ordinance 2008A-01, Section 13.D. Wells: a Water Status Report for 1- or 2-party private supplies and Group B systems; water samples may be taken.
- When
- Before sale. The district asks that applications be submitted 30 days before transfer; review takes about seven business days.
- Filed With
- Kitsap Public Health District, which prepares and issues both reports.
Confirm with the locality before you rely on it: Kitsap County source page.
Mason CountySeptic
Mason County requires a current inspection report by a certified operations and maintenance specialist before a septic property is sold.
- What Is Required
- A complete inspection report covering all system components, prepared by a certified O&M specialist. A pumping report alone no longer satisfies the requirement, even for a gravity system. Required by MCC 6.76.070(5).
- When
- Completed within the 12 months before the sale or transfer of ownership.
- Filed With
- Mason County Public Health, Environmental Health.
Confirm with the locality before you rely on it: Mason County source page.
Skagit CountySeptic
Skagit County requires an operations and maintenance inspection by a county-certified provider before any transfer of property with an on-site septic system.
- What Is Required
- An O/M inspection completed by a Skagit County Certified O/M Specialist, under Skagit County On-site Sewage Code Chapter 12.05.160. No new inspection is needed if one was completed in the prior six months.
- When
- Within six months of closing; the county suggests inspecting around the time an offer is made. The buyer may see the completed report before closing.
- Filed With
- A copy goes to the buyer and to the Health Officer; completed inspections appear on the county septic search site.
Confirm with the locality before you rely on it: Skagit County source page.
Snohomish CountySeptic
Snohomish County's Property Transfer Inspection rule, adopted in April 2026 and effective 1 November 2026, requires a septic inspection and a county-reviewed report before a sale closes.
- What Is Required
- A full septic inspection by a certified OSS contractor, tank pumping if the report recommends it, a record drawing or new site plan, and an application for a Report of Property Transfer issued by the health officer.
- When
- Inspection no more than 12 months before the transfer; report submitted and reviewed before closing. The issued report is valid 12 months and cannot be renewed once expired.
- Filed With
- Snohomish County Health Department; the seller then gives the buyer the reviewed report, maintenance records and a seller disclosure statement.
Confirm with the locality before you rely on it: Snohomish County source page.
Thurston CountySeptic
Thurston County runs a "Time of Transfer" process that every septic property must clear when the home is sold.
- What Is Required
- All tanks pumped and the system inspected by a county-certified septic professional, plus a system sketch, submitted on the county's Time of Transfer application. The county then issues an Evaluation Report listing any violations or deficiencies.
- When
- Pumping and inspection must be within the 12 months before the application is submitted. A corrected system can be re-applied within 12 months of the prior report date.
- Filed With
- Thurston County Public Health and Social Services, Environmental Health; pumping and inspection reports also appear in OnlineRME.
Confirm with the locality before you rely on it: Thurston County source page.
Only localities with a rule of their own are listed, and only where the rule was found on that locality’s own page. A county missing from this list may still have one that is not published — ask the county health office.
What a Septic Inspection CoversTank, distribution, pumps, drainfield, loading, records
A septic inspection is not part of a standard home inspection, and walking the yard with a probe is not an inspection. These are the parts an inspector is expected to open, look at and write up.
The Tank
Opened at the manhole, not just the inspection port. Sludge and scum measured, baffles or tees checked, effluent filter pulled and cleaned, walls and lid checked for cracks and leaks.
Distribution
Distribution box, drop boxes, diverter valves and the pipes between them, checked for level, roots, standing effluent and blockage.
Pumps and Controls
Pump tank, float settings, alarm test, control panel and run-time counters. On an advanced system, blowers, media and disinfection units too.
The Drainfield
Trenches, beds or drip lines walked for ponding, breakout, odor and soggy ground, plus grading and roof runoff that pushes water into the field.
Size and Loading
Permitted design flow in gallons per day or bedroom count, from the health department record, compared with how the house is actually being used and marketed.
The Paper Trail
Permits, as-built drawing, pump-out receipts, service contract, operator reports and any lab results. Missing records are a finding of their own.
What the Buyer’s Loan RequiresFHA, VA, USDA, conventional and 203(k)
State law decides what the inspection has to contain. The loan program decides whether the deal can close with what the inspection found. These rules are federal and apply in every state.
| Loan | When an Inspection Is Required | Well Distances | Water Testing | If It Fails |
|---|---|---|---|---|
| FHA | No septic inspection on every loan. One is required only if the appraiser sees evidence of failure, state or local law requires it, or the lender asks. A well water test is required in specific listed situations. | 4000.1 sets: well 10 ft from property line, 50 ft from septic tank, 100 ft from drainfield or seepage pit, 50 ft from non-watertight sewer lines. A July 2026 FHA waiver lets existing homes use local distances instead if water testing is documented. | Required for new construction, when the appraiser reports a well problem, when water is known unsafe, near landfills or farms, or when well-to-septic is under 100 ft. A disinterested third party samples; local or EPA limits apply; report under 180 days old at disbursement. | The system must meet Minimum Property Requirements before FHA will insure. Health and safety deficiencies are repaired before closing. A repair completion escrow is allowed only when work genuinely cannot be finished first, such as weather delays. |
| VA | No septic inspection on every loan. The appraiser looks first; a licensed inspection or local health authority approval is required only if problems show, soil conditions are known to be poor, or state, local, or lender rules require it. | Not specified by the program. VA Chapter 12 sets no well-to-septic or well-to-line distances and defers to the local or state health authority with jurisdiction. Secondary lender guides sometimes quote FHA's numbers, but VA itself does not. | Required when the home has a private well. A disinterested third party must collect and test the sample; the borrower may not. Local health authority standards apply, then state, then EPA. Lenders commonly treat the certification as valid for 90 days; confirm the window with the lender on the file. | A septic or well failure is a defective condition, so the home is unacceptable until repaired and further damage is ruled out. Repairs are generally completed before closing; veterans may request a VA waiver of repair requirements in limited cases. |
| USDA Guaranteed | Strictest of the five. A septic evaluation is required on every home with an individual system, by a HUD roster appraiser, health authority, licensed septic professional, or qualified home inspector. A water test is required on every well property. | USDA adopts HUD Handbook 4000.1 distances (10 ft to property line, 50 ft to septic tank, 100 ft to drainfield) or the actual distances accepted by the state or local health authority. The septic must sit entirely on the subject property. | Required on all wells, performed by the local health authority or a state-certified lab. State or local standards apply, or EPA maximum contaminant levels if none exist. The water analysis report must be no more than 150 days old at closing. | The system must be repaired so the home is decent, safe, and sanitary. A post-closing repair escrow is possible only if the work does not affect livability, costs 10 percent or less of the loan, is under contract, fully funded, and done within 180 days. |
| Conventional | Most permissive. Neither agency requires a septic inspection or water test on every loan. One is ordered only when the appraiser notes a problem, a nearby environmental hazard raises concern, or state, local, or lender rules require it. | Not specified by the program. Fannie Mae and Freddie Mac set no separation distances and instead require that utilities meet community standards, which in practice means the local health authority's rules govern. | Not routinely required. Fannie Mae calls a well certification sound judgment when the lender has reason to believe water may be contaminated, such as a well near a hazardous waste site. No contaminant list or validity period is published. | The lender decides whether the home is adequate security and what inspections are needed. Appraisals are typically made subject to repair or professional inspection, with evidence of corrective action kept in the loan file before closing. |
| FHA 203(k) | Same triggers as standard FHA, with one key difference: a known bad system does not have to be fixed by the seller first. Repairing or replacing a well or septic system is an eligible improvement that the loan itself can finance. | Same FHA Handbook 4000.1 distances apply (10 ft to property line, 50 ft to septic tank, 100 ft to drainfield). New or replacement systems installed with loan funds must meet local permitting as built. | Same as standard FHA: testing in the listed trigger situations, by a disinterested third party, against local health authority standards or EPA limits, with the report no more than 180 days old at disbursement. | This is the real advantage. Repair or replacement costs are escrowed at closing and the work is done afterward, so the deal does not die on a failed system. Limited 203(k) caps total rehabilitation at 75,000 dollars; Standard 203(k) has no such cap. |
Loan rules change and lenders add requirements of their own. Confirm with the lender on the file before you tell a client what is needed.
A Timeline That Protects the Closing DateSix steps, from listing to closing
Nearly every septic delay comes from the same place: the inspection was ordered late, and the report, the repair permit or the health department review ran past the contract date.
- 1
Before You List
Pull the permit and service history from the health department. A seller who knows what a buyer’s inspector will find can fix it or price it instead of renegotiating against a deadline.
- 2
Day One of Due Diligence
Order the inspection. Not day seven. In several states the inspector has up to ten business days to deliver the written report, and that clock runs inside your contingency.
- 3
Inspection Day
Power on, water on, lids reachable. Many inspectors want the tank pumped so the walls and baffles can be seen, which means booking the pumper the same day.
- 4
When the Report Lands
Read the parts that were not inspected and the reasons given. That list is usually where the next surprise is hiding.
- 5
Repairs and Permits
A repair or replacement normally needs a health department permit, and sometimes a soil evaluation. Build the review time into the extension, not just the contractor’s schedule.
- 6
Before Closing
Hand the operating permit, manual, service contract and maintenance log to the buyer, and make sure an advanced system has a licensed operator from day one.
What to Collect From the SellerEight documents to ask for at listing
Ask at listing. Every one of these is a document a lender, inspector or health department may ask for later.
- Construction and Operating Permit. Shows the permitted flow, the bedroom count the system was approved for, and any ongoing conditions.
- As-Built Drawing. Locates the tank, distribution box and field. Without it the inspection starts with a search.
- Pump-Out Receipts. Five years where the county sets a pumping interval, three years everywhere else.
- Service Contract. Required for advanced and aerobic systems in most states, and often required to be in force at transfer.
- Operator Service Reports. The last two years, including anything filed with the health department.
- Lab and Sampling Results. Where the permit requires sampling, or the system discharges to a stream or ditch.
- Well Records. Well completion report, depth, the most recent water test, and any treatment equipment.
- Repair Permits and Invoices. Any work on the tank, pump, field, control panel or well.
Homeowners keep all of this free in TankVault, and their septic company keeps it current. See the homeowner app.
Questions Agents Ask
Can a home inspector inspect the septic system?
It depends on the state. A growing number of states allow septic inspections only from someone holding an onsite sewage license, such as an operator, installer or soil evaluator, and an inspection by the wrong person may not satisfy the lender or the contract.
How long is a septic inspection good for?
There is rarely a date written into law, but lenders and buyers commonly treat an inspection older than six to twelve months as stale, and some states require the inspection to fall inside a set window before transfer.
Who pays for the septic inspection?
It is negotiable in nearly every state and the purchase contract decides. Sellers increasingly pay for an inspection before listing so the findings are theirs to handle rather than a renegotiation tool for the buyer.
Can you close on a house with a failing septic system?
On a government-backed loan, usually not until repairs are finished and verified. Conventional financing has more room, but the appraiser can still call out the condition and the lender can require it fixed before closing.
Does the septic permit transfer to the buyer?
In most states the operating permit runs with the property rather than the owner, and the upkeep duties travel with it. Some states and counties make the new owner file or register within a set number of days, and an advanced system usually needs a licensed operator from day one.
Why does the inspection report not say pass or fail?
Several states now forbid pass or fail wording and require the inspector to describe the condition of each part and what any problem means instead. It reads as less decisive and it is far more useful in a negotiation.
Does the well have to be tested when the house sells?
In most states only when the buyer, the contract or the loan asks for it. A handful of states require a test at transfer, and FHA, VA and USDA loans require one on any home served by a private well.
Where This Comes From8 sources for Washington
- WA DOH - On-site Sewage Systems (OSS)
- WAC 246-272A-0270 - Operation and maintenance, property transfer inspection
- WA DOH - On-site Sewage System Rule Revision (property transfer inspection effective Feb 1, 2027)
- Thurston County - Time of Transfer septic program
- WA Dept. of Ecology - Wells
- WAC 173-160-171 - Well location and setbacks
- Kitsap Public Health District - Water Status Reports
- Snohomish County Health Dept. - Buying or Selling Property with a Well
General information for real estate professionals, not legal advice. Washington rules change, and counties add their own, so confirm the requirement for a specific property with the agency above or the county health office.
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