Sewer Lateral Rules When You Sell in San Mateo County
Several San Mateo County cities require the private sewer lateral, the pipe from the house to the public sewer main, to be inspected or tested, and repaired if it fails, before a home sells. Burlingame, San Bruno, South San Francisco, the City of San Mateo and Pacifica publish point-of-sale rules on their own sites. News reports say Millbrae and Redwood City also require a lateral check at sale and that Belmont chose disclosure instead, but we found no published rule on those cities’ own pages, so confirm with each city.
The rule that applies depends on the city or sewer agency serving the parcel, not the mailing address.
These requirements matter in escrow because a failed test can mean permits, a contractor and a city sign-off before title can transfer. The table below sets out what each city publishes as of October 2026, followed by the order of work we suggest and what changes for condos. Rules change, so treat each row as a starting point and confirm with the city before you list.
City-by-city requirements at sale
| City | Sale trigger | What is required | How long a pass is good for |
|---|---|---|---|
| Burlingame | Transfer of property with buildings more than 25 years old | Water test, or air test in hillside areas, witnessed by a city representative; video not accepted; repairs completed and approved before title transfers | 10 years after a pass or a repair and retest; 25 years after full replacement |
| San Bruno | Sale of a home over 50 years old (enforced since May 8, 2015) | Lateral inspected and certified by the city before the sale; details are in the city’s requirement documents | Not stated on the city page |
| South San Francisco | Sale, for listing agreements in contracts as of June 21, 2022 | CCTV video inspection by a licensed contractor, submitted with a certificate application; repairs approved before title transfers | 10 years with no or partial repairs; 25 years after full replacement |
| City of San Mateo | Sale; also building permits for additions or remodels valued at $90,000 or more (effective December 1, 2020) | Owner inspects and tests the lateral and gives the results to the city | Exempt if inspected in the past 5 years with repairs done, or fully replaced under a city permit in the past 25 years |
| Pacifica | Transfer of ownership of property listed after January 1, 2012 (2012 policy) | Closed-circuit video of the full lateral; replacement if defects or leaks are found | 7 years; 20 years after full replacement |
| Millbrae | Listed as requiring inspection at sale in an undated San Mateo Daily Journal article; no published rule found on the city’s pages we searched | Confirm current rules with the city | Confirm with the city |
| Redwood City | Reported by The Almanac (March 2026) as having a point-of-sale ordinance; city page not checked | Confirm current rules with the city | Confirm with the city |
| Belmont | An undated San Mateo Daily Journal article reported that the council dropped an inspection-at-sale mandate in favor of seller disclosure; the city’s sewer pages we read mention no sale rule | Disclosure, per that article, which also reported a remodel inspection threshold rising from $50,000 to $200,000; final adoption not confirmed | Not applicable |
| Menlo Park | No inspection at sale, per The Almanac (March 2026) | No published rule found | Not applicable |
We could not find a published sale requirement for Hillsborough, San Carlos, Foster City, Daly City, Atherton, Woodside, Portola Valley or the unincorporated county. Finding no published rule is not proof that none exists, so ask the city or sanitary district that serves the parcel.
Burlingame: a witnessed test
Burlingame’s rule is one of the more hands-on. A contractor or plumber runs a water exfiltration test, or an air test where hillside pressure could damage the pipe, and a city representative must watch. The city does not accept video inspection for this purpose at present.
The test requires an encroachment permit and a testing fee from Public Works, and repairs need a plumbing permit. The city allows one free retest after a failure. It also states that it does not decide who pays; the buyer and seller do.
South San Francisco: video, a certificate and an escrow option
South San Francisco requires a CCTV video inspection by a licensed contractor that meets the city’s video report form, sent to the engineering division with the certificate application. The certificate must be in hand before title transfers, at the owner’s expense.
If it cannot be obtained before closing, the owner, agent or buyer can request an extension of up to 180 days, backed by a $10,500 deposit into an escrow account with the city that is refunded once the lateral passes. Exempt are properties with an active certificate, properties served by the Westborough Water District, and multi-unit buildings that share a lateral. HOA properties must otherwise comply.
San Bruno, San Mateo and Pacifica
San Bruno’s page is brief: homes over 50 years old must have the lateral inspected and certified by the city before sale, and the city points to its requirement documents for the method. Request those documents early, since they set the inspection standard.
The City of San Mateo’s code makes the owner responsible for the lateral from the building to the public main, including the connection, and requires a cleanout near the structure when a lateral is installed or replaced. The Public Works Director sets the inspection standards, and the city publishes an inspection form.
Pacifica’s 2012 administrative policy requires video of the full lateral and allows a time extension of up to 180 days after close of escrow with a $5,000 escrow deposit, or more for laterals over 50 feet. That policy is more than a decade old, so confirm the current method and deposit with the city’s wastewater staff.
How to schedule a lateral test inside a sale
- Identify the agency. Use the parcel record and the sewer bill to confirm which city or district serves the property.
- Check for a current certificate. A passing test, repair or replacement within the city’s validity window may exempt the sale, but you will need the paperwork.
- Test before listing if you can. Results then go into disclosures, and repairs do not compete with escrow deadlines. Our pre-listing inspection guide covers what else to order early.
- Get bids for any repair. Lining, spot repairs and full replacement differ in cost and in how long the certificate lasts.
- Write it into the contract. State who orders the test, who pays for repairs, any credit in lieu of repair, and what happens if work runs past closing.
- Keep the city’s sign-off for escrow. Escrow will usually need the certificate or approval before closing in a city that ties the rule to title transfer.
Diamond may refer you to partners we work with; you’re free to choose any provider.
What it can cost and how long it can take
None of the city pages we read publish repair costs. In The Almanac’s March 2026 report, a Daly City plumbing contractor estimated repairs at $8,000 to $10,000 on the lower end and full replacement at $20,000 or more, and described a typical lateral as three to four inches across and about 40 feet long. Treat those as one contractor’s figures, not a quote for your property.
The same report notes that permits, repairs and final inspections can take longer than a typical 30-day escrow. That is why the extension options in South San Francisco and Pacifica exist, and why testing before you list is usually the calmer path.
Condos, townhomes and shared laterals
Laterals serving several units raise different questions: who owns the pipe, whether the HOA has already tested it, and whether one unit’s sale can trigger the whole line. South San Francisco exempts multi-unit buildings that share a lateral but says HOA properties must otherwise comply.
Other cities do not address condos on the pages we read. If you are selling a unit, ask the HOA for any lateral testing records and ask the city how it treats shared lines before you set the escrow timeline.
Nearby comparisons
Across the county line, The Almanac reports that Palo Alto and Mountain View do not require lateral inspections as part of a sale, though Mountain View requires one for major projects such as an accessory dwelling unit. Morgan Hill does have a sale rule: properties more than 15 years old need a CCTV inspection by a city-listed contractor, and a failed lateral can be passed to the buyer through a notarized Transfer of Responsibility form with 180 days to repair.
In the East Bay, the regional program run by EBMUD works differently again; our Alameda County private sewer lateral guide explains it. For other statewide and local items due at sale, see our California point-of-sale requirements page.
Questions people ask
Do I need a sewer lateral inspection before selling in San Mateo County?
It depends on the city. Burlingame, San Bruno, South San Francisco, the City of San Mateo and Pacifica publish sale requirements. News reports say Millbrae and Redwood City have them too; confirm with the agency that serves your parcel.
What does Burlingame require for a sewer lateral test?
For property with buildings more than 25 years old, a water or air test witnessed by a city representative, with any repairs approved before title transfers. Video inspection is not accepted for the test.
Does San Bruno require a sewer lateral inspection at sale?
Yes. Since May 8, 2015, homes over 50 years old must have the lateral inspected and certified by the city before they are sold.
Can I close escrow in South San Francisco before the lateral is fixed?
The city allows an extension of up to 180 days if a $10,500 deposit is placed into an escrow account with the city, refundable once the lateral passes and the certificate is issued.
Does Belmont require a sewer lateral inspection when selling?
An undated San Mateo Daily Journal article reported that Belmont’s council chose seller disclosure over a mandatory inspection at sale. The city’s own sewer pages we read mention no sale rule, so ask Belmont Public Works before listing.
Who pays for sewer lateral repairs when a house sells?
The cities we checked leave that to the buyer and seller. It is negotiable, so write who pays for testing, repairs or a credit into the purchase agreement.
Does Hillsborough have a point-of-sale sewer lateral rule?
We did not find a published sale requirement for Hillsborough. Ask the town’s public works department before listing, since rules can be adopted or changed.
How long is a sewer lateral certificate valid?
It varies: Burlingame and South San Francisco give 10 years for a pass and 25 years after full replacement, and Pacifica’s 2012 policy gives 7 and 20 years.
This is general information, not legal advice. Sale requirements are set by each city’s ordinance, so confirm the current rule with the city’s public works department, and talk to a California real estate attorney if a repair obligation or holdback is in dispute.
Selling on the Peninsula and want the lateral question settled before buyers ask? Our San Mateo County selling guide covers the rest of the preparation, and you can talk with Diamond about selling. For taxes, transit and other local rules, see the San Mateo County guide.
Sources & notes
- City of Burlingame: Sewer lateral test ordinance
- City of San Bruno: Point of Sale Sewer Lateral Requirement
- City of South San Francisco: Point of Sale Ordinance Fact Sheet
- City of San Mateo Municipal Code 7.38.432: Private sewer laterals
- City of San Mateo: Private Sewer Lateral Ordinance
- City of Pacifica: Administrative policy on sewer lateral compliance certificates (revised January 27, 2012)
- The Almanac: What Peninsula homeowners need to know about sewer inspections before selling (David Goll, March 16, 2026)
- City of Belmont: All About Sewers (owner responsibility for laterals; Ordinance 1070)
- San Mateo Daily Journal: Belmont drops sewer fix home sale mandate (undated in the version we read)
- City of Morgan Hill: Utility Inspection at Property Sale
Last reviewed October 2026 by Matthew Martinez.
