San Mateo County Assessor Property Search & Tax Lookup 2026

by
San Mateo County, California • verified August 15, 2026

Find the Correct San Mateo Property Record

San Mateo County property research is split between the Assessor, Property Maps, Treasurer-Tax Collector and County Clerk-Recorder. Start with the property address or APN, then move to the office that controls the value, bill, deed, exemption or appeal you actually need.

This guide explains address and parcel lookup, RecorderWorks name searches, 2026 assessment deadlines, Prop 8 review, formal appeals, BOE-266 Homeowners’ Exemption, PCOR requirements, supplemental taxes and common search problems.

Choose My Search Search Step by Step 2026 Deadlines
Assessment date January 1, 2026 Important valuation date for the 2026 assessment cycle.
Informal value review October 31, 2026 Deadline for the Assessor’s 2026 Decline in Value request.
Regular appeal November 30, 2026 Formal Assessment Appeals Board deadline for regular assessments.
Secured tax bill Mailed by November 1 First installment is due November 1 and subject to the December delinquency deadline.

Fast Answer: Where Should You Search?

Property address, APN or maps: start with the official San Mateo County Property Maps system. Property tax bill or payment: use the Treasurer-Tax Collector. Deed, lien or recorded-document history by a person’s or business’s name: use RecorderWorks. Assessment value, exemption or informal value review: use the Assessor Division.

Independent guide: AssessorPropertySearch.org does not store San Mateo County parcel records, accept property-tax payments or file appeals. Complete sensitive or legally significant actions only through the official county resources explained below.

Choose the Correct San Mateo County Property Tool

The fastest route depends on the result you need. The Assessor, Tax Collector and Recorder are connected, but their databases answer different questions.

APN

Address, APN, parcel map or assessment question

Use the Assessor and Property Maps workflow to identify the parcel, retrieve Assessor maps, review assessment information and find the parcel number needed for other county tasks.

Official San Mateo County Assessor / GIS Open Property Maps
$

Tax bill, installment, payment or delinquency

Use the Treasurer-Tax Collector for current secured taxes, payment status, penalties, installment deadlines, online payment and supplemental bills.

Official County of San Mateo Tax Collector Open Tax Collector
DOC

Deed, lien, release or recorded-document search

Use RecorderWorks to search the Grantor/Grantee index by name, document number, recording date, document type, APN and other supported fields.

Official San Mateo County Clerk-Recorder Open RecorderWorks
AAB

Formal assessed-value dispute

Use the Assessment Appeals Board when you need an independent formal appeal rather than only an informal Assessor review.

Official San Mateo County Assessment Appeals Open Assessment Appeals
Wrong-office warning: the Assessor determines assessed value but does not process your tax payment. The Tax Collector collects taxes but does not change your assessment. The Recorder maintains recorded title-related documents but does not decide the assessed value.

How to Search San Mateo County Property Records

Use this sequence when you have a property address but are not sure which county system you eventually need.

Choose the record type

Decide whether your final task is parcel identification, assessed value, taxes, a recorded deed, an exemption or an assessment appeal.

Search the physical address

Open Property Maps and search the actual property location. For condominiums or multi-unit buildings, do not assume the first building result is the exact separately assessed unit.

Save the APN

The 9-digit Assessor Parcel Number is the most useful identifier for tax, map, appeal, mailing-address and Recorder research.

Confirm the matching parcel

Check the parcel location and available map context. Compare the APN with a tax bill, deed or closing document when the property has multiple units or nearby parcels.

Move to the office that controls your next action

Use the APN in the tax system for a bill, RecorderWorks for document research, the Assessor for value/exemption questions or the AAB portal for a formal appeal.

Verify the year or document before acting

Confirm the assessment year, fiscal year, installment, recording date and parcel before paying, appealing or ordering a document.

What San Mateo County Property Records Actually Show

Record
Useful for
Important limitation
APN
Connecting parcel, map, tax, appeal and recorder research.
Parcel splits or combinations can create new parcel numbers.
Assessed owner
Identifying the name carried on the assessment roll.
It is not a substitute for the latest deed or title research.
Assessed value
Property-tax calculations and assessment appeal research.
It is not the same as a listing price, lender appraisal or final tax bill.
Exemption
Understanding reductions currently reflected in taxable assessment data.
A newly filed claim may not appear immediately.
Assessor map
Parcel identification and map references.
It is not a legal boundary survey.
Recorded map
Parcel/subdivision map research.
Later documents, corrections or easements may also matter.
Tax bill
Amount due, installments, penalties and special charges.
The Tax Collector does not determine the underlying assessed value.
Recorder index
Deed, mortgage, lien, release and map references.
Images are not included in the online index.
Legal-use warning: use recorded documents, title research and a licensed surveyor where ownership, easement or boundary conclusions matter. Assessor/GIS information is primarily an assessment and research tool.

Assessor Maps, Parcel Maps and Recorded Maps

The official Property Maps portal can retrieve Assessor maps and available recorded subdivision or parcel maps without turning the article into a fake map-search tool.

Find maps from a property

  • Search by address or APN.
  • Open the matching parcel.
  • Select Assessor Map for the assessment map.
  • Select All Available Recorded Maps for connected recorded maps.
  • Open the map name to download the available map.

Find a map from its reference

  • Assessor maps can be searched by book and page.
  • Parcel Maps can be searched by volume/page.
  • Subdivision Maps can be searched by volume/page.
  • Official printed copies can also be obtained from the Recorder Division.
Zoning is a separate question: an Assessor parcel map is not the county or city zoning determination. For development, use the planning department responsible for the incorporated city or unincorporated county area.
Official San Mateo County Assessor Maps Review Map Search Methods

San Mateo County Property Tax Lookup

Once the task becomes “how much do I owe?” or “did my payment post?”, use the Treasurer-Tax Collector rather than the Assessor.

What to check before paying

  • Correct property/APN.
  • Correct fiscal year.
  • First vs second installment.
  • Prior-year delinquency.
  • Supplemental bill vs annual secured bill.
  • Any penalty or redemption amount.
  • Payment method and service fee.

Why the tax bill can exceed 1%

The Assessor establishes the January 1 value. The tax amount typically begins with the basic 1% levy, then can include voter-approved indebtedness and special charges added by cities or local districts.

A sewer, district or other special charge on the tax bill is not necessarily an Assessor valuation issue. Identify the specific charge before deciding which office to contact.
Official San Mateo County Treasurer-Tax Collector View Property Tax Services

Property Tax Payment Fees, Deadlines and Postmark Rules

Payment method
Current county fee
Micro-level check
Online eCheck
Free
Verify bank routing/account information before submission.
Online credit card
2.35% service fee
Current county contact page lists a $1.95 minimum transaction fee.
PayPal
2.35%
Confirm the displayed fee before final submission.
PIN debit
$2.95
County lists this as an in-person option.
Mailed check
No card-service fee
The USPS postmark controls timeliness, not a private postage-meter date.
Online deadline: the county says electronic payments are accepted through 11:59 p.m. Pacific Time on the applicable delinquency date.
Mailed-payment trap: California law requires the Tax Collector to use a United States Postal Service postmark. A private meter date does not substitute for the USPS postmark.

Use the official Tax Collector page first; it links to the county’s current payment processor.

Official Tax Collector payment guidance Review Payment Methods

San Mateo County 2026–27 Property Tax Timeline

January 1, 2026 — lien and valuation date

The Assessor establishes the property value used for the upcoming secured-tax cycle, subject to California reassessment and exemption rules.

July 1, 2026 — 2026–27 fiscal year begins

The county tax fiscal year runs July 1 through June 30.

July 2–November 30 — regular assessment appeal period

Regular real and personal property assessment appeals for 2026 must be filed within this county window.

October 31, 2026 — informal Decline in Value deadline

This is the Assessor’s current deadline for an informal review of the January 1, 2026 assessed value.

By November 1 — secured tax bills mailed

The Tax Collector says secured tax bills are mailed by November 1.

November 1 — first installment due

The first secured installment becomes due and payable.

November 10 — informal-review decision checkpoint

County appeal guidance recommends filing a formal appeal when an informal Decline in Value result has not been received by this point and you need to preserve appeal rights.

November 30, 2026 — regular appeal deadline

The Assessor’s informal process does not extend this formal filing period.

December 10 — first-installment delinquency deadline

A 10% penalty applies after the deadline, subject to the county’s weekend/holiday next-business-day rule.

February 1, 2027 — second installment due

The second secured installment becomes due and payable.

April 10 — second-installment delinquency deadline

A late second installment normally receives a 10% penalty plus a $40 cost.

July 1 after default

The county currently lists a $35 redemption fee plus a 1.5% monthly redemption penalty for defaulted secured parcels.

2026 Decline in Value Review: Prop 8 Informal Route

A temporary Proposition 8 reduction can apply when the January 1 market value falls below the property’s factored base-year value. The Assessor reviews each request individually.

Current online application asks for

  • Assessor Parcel Number.
  • Property address.
  • Date of purchase.
  • Current assessed value.
  • Your opinion of market value as of January 1, 2026.
  • Facts supporting the lower value.
  • Supporting document upload.
  • Owner contact and mailing information.

Prepare useful value evidence

  • Comparable sales relevant to January 1, 2026.
  • Differences in size, condition, lot and location.
  • Photos of material property-condition problems.
  • Repair estimates for significant defects.
  • Recent purchase documents when relevant.
  • A clear January 1 market-value conclusion.
Prop 13 vs Prop 8: the factored base-year value is generally limited to annual inflation growth of no more than 2%, but a temporary Prop 8 assessed value can rise by more than 2% during market recovery as long as it does not exceed the applicable factored base-year value.
Do not let the informal review consume your formal deadline. If the informal result is not received before the county’s November checkpoint and you still disagree with value, use the formal AAB filing process before November 30 to preserve appeal rights.
Official San Mateo County Assessor Property Tax Relief Open 2026 Decline in Value Review

File a Formal San Mateo County Assessment Appeal

The Assessment Appeals Board is separate from the Assessor and provides the formal dispute process.

Regular assessment By Nov. 30
Supplemental / escape Generally 60 days
Calamity reassessment Generally 6 months
Application fee $30

Before submitting

  • Confirm the APN.
  • Confirm the assessment year.
  • Use one parcel and one year per application.
  • Identify the roll value being challenged.
  • State your opinion of value.
  • Select the applicable factual basis for the appeal.
  • Attach the Supplemental/Escape Notice when that type of assessment is being appealed.
  • Pay the current $30 non-refundable filing fee.
  • Keep the appeal number after the application is accepted.
  • Continue paying property taxes on time while the appeal is pending.

After the appeal is accepted

Stage
What happens
User action
Clerk review
The application is reviewed for validity and completeness.
Respond promptly if the Clerk identifies a deficiency.
Appeal number
Accepted applications receive an appeal number.
Use it in all AAB correspondence.
Pre-hearing
A pre-hearing conference can begin the evidence-exchange process.
Organize valuation evidence before the conference.
Hearing notice
The county says the hearing notice is provided at least 45 days in advance.
Calendar the date immediately.
Evidentiary hearing
You and the Assessor present evidence to the Board.
Focus on market value, base-year value or the actual disputed assessment issue.
Decision
The Board can adopt your value, the Assessor’s value or another supported value.
Keep the written decision with tax and appeal records.
Processing time: current county guidance warns that the full appeal process can take up to two years depending on volume and case complexity. Filing an appeal does not stop normal property-tax payment deadlines.
Written Findings of Fact: county preparation guidance currently lists a fee of $500 per hour of hearing time or fraction thereof. This is mainly relevant to taxpayers considering Superior Court review, so understand its purpose before requesting it.

The county’s main Assessment Appeals page now directs applicants to a new secure online portal for applications, status, schedules and forms.

Official San Mateo County Assessment Appeals Board
Review Current Appeal Instructions Open Secure AAB Portal

2026 Homeowners’ Property Tax Exemption — BOE-266

The California Homeowners’ Exemption can remove up to $7,000 of assessed value from a qualifying principal residence. Filing the claim is free.

Who may qualify?

  • An owner or co-owner occupying the dwelling as the principal residence.
  • A qualifying purchaser named in a contract of sale.
  • A qualifying single-family residence.
  • A qualifying condominium or cooperative unit.
  • Certain houseboats, manufactured homes and other taxable dwellings.

Who should not use the claim?

  • A property intended to be rented.
  • A vacant and unoccupied dwelling.
  • A vacation home.
  • A secondary residence that is not the claimant’s principal residence.
  • A former residence after eligibility has ended.

BOE-266 asks for

  • Parcel number.
  • Address of the dwelling.
  • Owner name.
  • Required Social Security number information.
  • Co-owner/spouse information when applicable.
  • Date acquired.
  • Date the property became the principal residence.
  • Information about another California principal residence when applicable.
  • Owner-occupant certification and signature.
Sensitive-information warning: BOE-266 contains Social Security number fields and is marked as not subject to public inspection. Submit it only through the Assessor’s authorized process. Do not send Social Security numbers to this website.

2026 filing rules from BOE-266

Situation
Current form rule
Full annual exemption
File by 5 p.m. February 15 when eligible.
Late annual claim
Claims filed February 16 through 5 p.m. December 10 can generally receive 80% of the exemption.
New owner
A new owner must file a new claim even when the property was already receiving the Homeowners’ Exemption.
Supplemental assessment
For a qualifying full supplemental exemption, filing generally must occur within 30 days after the Notice of Supplemental Assessment.
New owner / new construction supplemental
The owner generally must occupy the property as the principal residence within 90 days of the ownership change or construction completion.
Unrecorded contract
Attach a copy if you are buying under an unrecorded contract and the Assessor does not already have it.
Property becomes ineligible
Notify the Assessor promptly. The form describes a statutory penalty for failure to report loss of eligibility.
Once granted: the BOE-266 instructions say the exemption remains in effect until terminated. A new claim is needed after termination to regain eligibility.
Official San Mateo County Homeowners’ Exemption forms Open BOE-266 Forms

New Owner: Preliminary Change of Ownership Report — BOE-502-A

The PCOR is completed by the transferee/buyer and generally accompanies a conveyance filed with the County Recorder.

Core PCOR fields

  • Buyer/transferee name and mailing address.
  • Assessor Parcel Number.
  • Seller/transferor.
  • Physical property address.
  • Buyer email and daytime phone.
  • Principal-residence intent and occupancy date.
  • Where property-tax information should be mailed.

Transfer information

  • Spouse or registered domestic partner transfer.
  • Parent/child or grandparent/grandchild transfer.
  • Cotenant death.
  • Age-55 replacement residence.
  • Severely disabled replacement residence.
  • Wildfire/natural-disaster replacement residence.
  • Trust, financing, lease or proportional-interest situations.
PCOR is not a reassessment-exclusion approval. Checking a possible exclusion on the report helps the Assessor understand the transfer, but a separate claim form can still be required to receive a particular exclusion.
Recording penalty: the County Clerk-Recorder currently states that when a required PCOR is not submitted with the conveyance, a $20 penalty fee is added to the recording fee.

The PCOR is confidential and not subject to public inspection. Use the county’s official ownership-form page for the current BOE-502-A PDF or electronic submission option.

Official San Mateo County Change in Ownership Forms Open BOE-502-A Forms

Other Ownership Changes Have Different Reporting Deadlines

Ownership event
Form / route
Current county timing
Recorded conveyance
BOE-502-A PCOR
Filed with the conveyance at recording when required.
Unrecorded ownership change
BOE-502-AH Change of Ownership Statement
Generally within 90 days of the ownership change.
Assessor requests ownership statement
BOE-502-AH
Generally within 90 days of the request to avoid penalty.
Death of real property owner
BOE-502-D
Generally within 150 days of death to avoid penalty.
Prop 19 transfers: parent-child, grandparent-grandchild and qualifying base-year-value transfers have separate eligibility rules and claim forms. Do not assume the PCOR alone completes the exclusion claim.

Why a New Owner Can Receive a Supplemental Tax Bill

A supplemental assessment is created when a change in ownership or completed new construction produces a new assessed value outside the ordinary annual roll.

Supplemental assessment

The Assessor calculates the difference between the prior value and the new value, then prorates the assessment for the relevant portion of the fiscal year.

  • It is separate from the annual secured assessment.
  • It can create a separate tax bill.
  • The bill can arrive after closing.
  • An escrow account may not automatically pay it.

Why two supplemental bills can appear

The Assessor explains that ownership changes or new construction occurring from January through May can affect two fiscal-year rolls and therefore create two supplemental assessments/bills.

Do not automatically treat the second bill as a duplicate.

Supplemental bill deadlines depend on mailing date

Bill mailed
First delinquency date
Second delinquency date
July through October
December 10
April 10
November through June
Last day of the month following mailing
Four months after the first delinquency date
Example: the Tax Collector explains that a supplemental bill mailed in February has a first-installment delinquency date of March 31 and a second-installment delinquency date of July 31. Always use the actual dates printed on your supplemental bill.
Official San Mateo County supplemental tax information Review Supplemental Tax Rules

Search Deeds, Liens and Recorded Property Documents

RecorderWorks is more powerful when you know exactly which index field to use.

Search field
Use it when
Micro-level tip
Name
You know a grantor, grantee, business or other indexed party.
Use LAST NAME FIRST NAME; add a partial first name to reduce timeout risk.
Document Number
A title report, deed or other source gives the recording number.
Current help says modern full document numbers begin with the four-digit year.
Recording Date
You know approximately when a transaction was recorded.
Add document type to narrow a large period.
Document Type
You need a deed, deed of trust, lien, release, easement, map or similar record.
Combine with a date range.
Parcel Number
You already know the APN.
Enter the 9 digits without dashes.
Book / Page or Map
Older documents or mapped records give a formal recording reference.
Confirm document type before ordering a copy.
Records before 1985: RecorderWorks notes that records recorded before 1985 can only be retrieved using the document number and/or recording date rather than the modern name-index workflow.
Tax bill owner names: RecorderWorks explains that the latest deed can contain all grantees while a tax bill may display only the first listed name. Use the recorded deed when the complete legal ownership list matters.
Online index limitation: document images are intentionally excluded from the public online Grantor/Grantee database. Identify the document in RecorderWorks, then order or inspect the recorded copy through the Recorder when needed.
Official San Mateo County RecorderWorks Search Recorded Documents

Correct a Mailing Address, Ownership Record or Property Detail

Mailing address is wrong

Use the Assessor’s Change of Mailing Address process. List the affected APN and new mailing details.

Physical situs address is wrong

The Assessor’s mapping guidance says physical situs-address changes come from the planning/building authority responsible for the jurisdiction.

Ownership display is outdated

Confirm the deed was recorded, then contact the Assessor about the ownership update rather than recording a duplicate deed simply to change the display.

Moving out of a principal residence? review whether the Homeowners’ Exemption must be terminated. BOE-266 places responsibility on the owner to notify the Assessor when eligibility ends.
Official San Mateo County Assessor Change Mailing Address

San Mateo County Property Search Troubleshooting

Problem
Likely reason
Best next step
Address returns nothing
Formatting, unit number or situs-address mismatch.
Simplify the address, remove unit details, use the map or search APN.
Building appears but condo unit does not
One building contains multiple separately assessed parcels.
Confirm unit APN from deed, tax bill or closing documents.
Cannot search Assessor by broad owner name
The parcel/map workflow centers on address and APN.
Use RecorderWorks for name-indexed recorded documents.
Recorder name search times out
The name is common or search is too broad.
Add a partial first name and date range.
Recent deed is recorded but Assessor still shows old owner
Recording and assessment databases update on different schedules.
Keep the recording number and contact the Assessor about processing status.
Tax bill cannot be found in August
The new secured bill may not yet have been issued.
Remember annual secured bills are mailed in the fall; verify APN and tax year.
Assessed value rose more than 2%
Possible Prop 8 restoration, new construction, change in ownership or another reassessment event.
Compare prior and current notices and ask the Assessor which valuation rule caused the change.
Tax bill shows unexpected charges
Voter-approved debt or special district/city charges.
Identify the charge before deciding which agency to contact.
Two supplemental bills arrive
A January–May ownership change or construction completion affected two fiscal years.
Compare each bill with the supplemental assessment notice before treating either as a duplicate.
Deed image is missing
RecorderWorks does not publish public document images in the index.
Use the document number to request or inspect the recorded copy.
Informal value review remains pending
Assessor review has not finished before the formal deadline.
Use the county’s November checkpoint and file a formal appeal before November 30 when needed to preserve rights.
GIS line conflicts with fence
Online parcel mapping is not a survey.
Review recorded documents and obtain a licensed survey when boundary accuracy matters.

San Mateo County Property Offices and Contact Scripts

Office
Use it for
Current contact
Assessor Division
Assessment value, exemptions, ownership changes, mailing addresses, maps and property data.
555 County Center, 3rd Floor, Redwood City, CA 94063
650-363-4500
assessor@smcacre.gov
Mon–Fri, 8 a.m.–5 p.m.
Treasurer-Tax Collector
Tax bills, payment status, penalties, supplemental bills and delinquency.
555 County Center, 1st Floor, Redwood City, CA 94063
866-220-0308
taxmaster@smcgov.org
Mon–Fri, 9 a.m.–5 p.m.
County Clerk-Recorder
Deeds, liens, releases, maps, recording and recorded copies.
555 County Center, 1st Floor, Redwood City, CA 94063
650-363-4500
recorder@smcacre.gov
Mon–Fri, 8 a.m.–5 p.m.
Assessment Appeals Board Clerk
Formal appeals, application status and hearing questions.
500 County Center, Redwood City, CA 94063
650-363-4573
AAB@smcgov.org

Assessor call script

“I am calling about APN [number] at [address]. I need help understanding the 2026 [assessed value / ownership / exemption / map / mailing-address] record. The specific issue is [one sentence].”

Tax Collector call script

“I am calling about APN [number] for fiscal year [year]. I need to confirm the [bill / payment / penalty / supplemental / delinquent] amount and current status.”

Recorder call script

“I found RecorderWorks document [number], recorded on [date], under [name]. I need the correct method for obtaining the recorded copy.”
Visit planning: ACRE states that walk-ins are welcome but subject to time and space availability, and appointments are available. Bring the APN and the exact notice, bill or document connected with your question.

Official San Mateo County Links by Final Task

Use these after identifying the correct task. The article explains the process; the links below are for live lookup, filing, payment or confirmation.

Assessor

Assessment values, forms, exemptions, ownership and mapping help.

Open Assessor

Property Maps

Address/APN parcel search, Assessor maps and available recorded maps.

Search Property Maps

Tax Collector

Secured bills, payments, due dates, penalties and supplemental taxes.

Open Tax Collector

RecorderWorks

Grantor/Grantee, document number, APN, date and document-type searches.

Search RecorderWorks

Decline in Value

Informal review of the January 1, 2026 assessed value.

Open Value Review

Assessment Appeals

Formal application, status, hearing and appeal information.

Open AAB

Before You Rely on the Result

  • The APN matches the intended property.
  • The physical address matches.
  • The correct assessment year or fiscal year is selected.
  • The tax bill is from the official Tax Collector workflow.
  • The installment and delinquency date are correct.
  • The Assessor value has not been confused with the final tax amount.
  • The Recorder document matches the correct parties and parcel.
  • A tax-bill owner name has not been treated as a complete title report.
  • An informal value review has not caused you to miss the formal November 30 deadline.
  • A GIS or Assessor map has not been used as a legal survey.

San Mateo County Assessor Property Search FAQs

How do I search San Mateo County property records by address?

Use the official Property Maps portal, choose the address-search option, enter the physical property address and open the matching parcel. Save the 9-digit APN so you can use it for tax, Recorder and appeal research.

Can I search San Mateo County property records by owner name?

For recorded-document research, use RecorderWorks. Enter a person as last name followed by first name or search a business name. A RecorderWorks name result is recorded-document history and should not be treated as a guaranteed list of everything that person currently owns.

How do I search a San Mateo County parcel by APN?

Use the official Property Maps portal and choose Find Parcels by APN. RecorderWorks also accepts parcel-number searches and currently instructs users to enter the 9-digit APN without dashes.

Where do I look up and pay San Mateo County property taxes?

Use the San Mateo County Treasurer-Tax Collector. The official Tax Collector site provides the secured tax-payment route, due-date information, payment methods, penalties and supplemental-tax guidance.

What is the 2026 San Mateo County regular assessment appeal deadline?

The regular 2026 Assessment Appeals Board filing period runs through November 30, 2026. Supplemental and escape assessments generally use separate 60-day notice-based filing periods.

What is the 2026 Decline in Value deadline?

The Assessor’s informal Decline in Value deadline for the January 1, 2026 assessed value is October 31, 2026. The informal process does not automatically extend the November 30 formal appeal deadline.

How much does a San Mateo County assessment appeal cost?

The county currently charges a $30 non-refundable fee per appeal application. A separate application is required for each parcel and each roll year.

How much is the San Mateo County Homeowners’ Exemption?

The California Homeowners’ Exemption can reduce assessed value by up to $7,000 for an eligible principal residence. The 2026 BOE-266 instructions provide the February 15 full-exemption deadline and late-filing rules.

Where can I find a San Mateo County deed or lien?

Use RecorderWorks to identify the recorded document by name, document number, date, type, APN or another supported index field. The public online index does not display document images, so obtain the recorded copy separately when needed.

Is the San Mateo County Assessor parcel map a legal survey?

No. Assessor and GIS parcel maps are research tools. Use recorded maps, deed information and a licensed surveyor when a legal boundary, easement or encroachment determination matters.

Best Next Step

Start with the physical address and save the APN. Then use the office that controls your final task: the Assessor and Property Maps for parcel/value information, the Tax Collector for money due or paid, RecorderWorks for recorded documents, and the Assessment Appeals Board for a formal valuation dispute.

For 2026 value disputes, protect the October 31 informal-review and November 30 formal-appeal deadlines. For payments, verify the fiscal year, installment and APN before submitting money.

Property Search Smart Helper

Find the Right Property Record, Tax Bill, Deed or Assessor Search Route

Use this helper before searching county property records. It helps you choose the right office, prepare the right details, avoid wrong-office mistakes, and review property records safely.

Official-source focused Use county assessor, appraiser, auditor, tax collector, treasurer, recorder, clerk, GIS and appeal resources where available.
Not legal or tax advice Always confirm values, taxes, deeds, exemptions, appeals and deadlines with the official county office.
Works across states Designed for APN, PIN, parcel number, STRAP, folio, account number, GIS map and deed-record searches.

Property Search Route Finder

Choose what you have and what you want to find. The tool will suggest the best search route and common mistake to avoid.

Copied.

Parcel / APN / PIN Format Helper

Parcel numbers are formatted differently by county. Try these variations if your official search does not return results.

This tool does not send or store your entry. It only creates search-format ideas on this page.
Copied.

Assessor, Tax Collector, Recorder or GIS?

Select your issue and this tool will show the office that usually handles it.

Choose an option above
This finder helps prevent wrong-office mistakes. Exact office names vary by state and county.

Simple Property Tax Estimate Helper

This is a general estimate only. State and county tax rules differ, so always verify final bills with the official tax collector, treasurer or county tax office.

Copied.

Exemption / Appeal Readiness Checklist

Use this before applying for an exemption or challenging a value. Missing proof is one of the biggest reasons users waste time or miss deadlines.

Property Record Review Checklist

Review these fields before relying on any assessor, appraiser, auditor, property appraiser, tax or deed record.

Official-source and accuracy note: This helper is for educational use only. Property values, tax bills, deeds, exemptions, GIS boundaries and appeal deadlines can change. Always confirm final information with the official county assessor/appraiser/auditor, tax collector/treasurer, recorder/clerk, GIS office or appeal board.