Alameda County Property Tax: Pay, Search, Due Dates & Exemptions
If you searched for “www Alameda County org property tax” or an older acgov.org/propertytax address, the current Alameda County property-tax system is operated by the Treasurer-Tax Collector through the county’s official property-tax portal.
Use the Tax Collector for bills, balances, payments and receipts. Use the Alameda County Assessor for property value, parcel information and exemptions. Assessment appeals are filed through the Assessment Appeals Board rather than the Tax Collector.
Quick Answer: Alameda County Property Tax
For a real-property tax bill, balance, payment or receipt, start with the Alameda County Treasurer-Tax Collector. The official portal separates secured real property, supplemental bills, unsecured taxes and prior-year delinquent taxes.
For assessed value, parcel information, exemptions, change-of-ownership questions or property characteristics, use the Alameda County Assessor. Do not assume the Assessor can accept your tax payment.
- Open the official Alameda County property-tax page.
- Choose secured, supplemental, unsecured or prior-year delinquent taxes.
- Search the correct property or account.
- Verify the fiscal year, installment and posted payments.
- Review the payment method and convenience fee.
- Submit payment only through the county-authorized route.
- Save the confirmation and verify the payment later appears in the account.
The Tax Collector controls billing and collection. The Assessor controls assessment and many exemption matters. Use the office that matches the task.
What Happened to Www Alameda County Org Property Tax?
Older county publications and search results commonly reference www.acgov.org/propertytax. Alameda County now also operates its property-tax pages through the alamedacountyca.gov domain and the dedicated propertytax.alamedacountyca.gov portal.
Choose secured, supplemental, unsecured or prior-year delinquent taxes.
Open official tax portalSearch by property address or parcel number and review available bills and tax-account information.
Open official searchUse for assessed value, parcel maps, exemptions and assessment-related questions.
Open official AssessorPayment safety: do not choose a property-tax payment website simply because it appears first in search results. Start from the county’s own property-tax page and follow the payment link from there.
Which Alameda County Office Handles What?
| Task | Correct Office | What It Handles |
|---|---|---|
| Search or pay property tax bill | Treasurer-Tax Collector | Current secured, supplemental and unsecured bills, payment status and collections. |
| Check assessed value | Assessor | Property assessment, ownership information, parcel records and valuation. |
| Homeowners’ or Disabled Veterans’ Exemption | Assessor | Eligibility guidance, claim forms and exemption administration. |
| Tax rate or special assessment question | Auditor-Controller / levying agency | Tax Rate Area information, debt-service rates, fixed charges and special assessments. |
| Formal assessment appeal | Assessment Appeals Board / Clerk of the Board | Appeal applications, hearings and appeal records. |
| Deed or recorded lien search | Clerk-Recorder | Recorded deeds, liens and other real-property documents. |
| Delinquent prior-year tax | Treasurer-Tax Collector | Current redemption amount, installment-plan information and tax-defaulted accounts. |
The Alameda County Assessor does not replace the Treasurer-Tax Collector for payment. A parcel or value record is not the same as a live tax-account balance.
How to Search an Alameda County Property Tax Bill
The county’s current secured and supplemental tax search supports lookup by property address or Assessor’s Parcel Number (APN). The parcel number should be entered in the format required by the county portal.
Use this system for real-property secured, supplemental and available prior-year tax information.
Search Alameda County Property TaxesParcel record ≠ tax balance. The Assessor’s parcel viewer is useful for property and assessment data. Use the Treasurer-Tax Collector system for the current amount due and payment status.
How to Pay Alameda County Property Tax
Alameda County publishes online, phone, mail and in-person payment routes. Payment availability can depend on the tax type and account status.
The county’s current payment and convenience-fee pages state that an electronic check from a checking or savings account has no convenience fee.
The county’s current convenience-fee page lists a 2.3% credit-card convenience fee. Review the fee shown before submitting.
The property-tax telephone system is available 24 hours a day, seven days a week for information and eligible card payments.
Mail using the county’s current bill instructions and include the correct payment coupon or parcel/account information.
1221 Oak Street, Room 131, Oakland, CA 94612. County-listed hours are 8:30 a.m.–5:00 p.m. weekdays, excluding holidays.
The county publishes a drop box at the Oakland Administration Building and a mail slot at its Hayward Business License Office.
Fee conflict to check: the county’s current main property-tax page and dedicated convenience-fee page list a 2.3% credit-card fee, while another county online-payment instruction page still displays 2.5%. Review the fee presented by the official payment system immediately before authorizing a card transaction.
- Confirm the parcel or account belongs to the correct property.
- Verify the fiscal year and installment.
- Check whether a mortgage servicer already paid.
- Review the current amount due.
- Check the payment method and displayed fee.
- Confirm the deadline and cutoff rule.
- Save your payment confirmation.
- Recheck the account after processing.
CountyPropertyTaxes.us does not accept Alameda County tax payments. Do not enter bank-account, card, portal-password, Social Security or taxpayer-PIN information on this informational website.
Alameda County Property Tax Due Dates
Alameda County uses California’s fiscal-year property-tax calendar. Secured real-property taxes are generally paid in two installments, while supplemental and unsecured taxes can use different deadlines.
| Date | Event | What It Means |
|---|---|---|
| January 1 | Annual lien date | Property is assessed as of 12:01 a.m. for assessment purposes. |
| February 15 | Full-value exemption filing deadline | Important deadline for Homeowners’, Disabled Veterans’ and several other exemption claims. |
| July 1 | Fiscal year begins | California county property-tax fiscal year runs July 1 through June 30. |
| July 2 | Regular appeal filing opens | Annual assessment appeal applications may be filed with the Assessment Appeals Board. |
| August 31 | Regular unsecured tax deadline | For 2026–27, Alameda County stated unsecured property tax was due by 5 p.m. August 31, 2026. |
| September 15 | Regular assessment appeal deadline | The 2026 regular annual appeal filing window has passed as of this guide’s September 21, 2026 review date. |
| November 1 | First secured installment due | First installment for the secured annual tax bill is due. |
| December 10 | First installment delinquency / late exemption deadline | First secured installment becomes delinquent after 5 p.m.; also an important late-exemption filing date. |
| February 1 | Second secured installment due | Second installment becomes due in the following calendar year. |
| April 10 | Second installment delinquency date | Second installment normally becomes delinquent after 5 p.m. Weekend and legal-holiday rules can extend the no-penalty deadline to the next business day. |
Supplemental bills use their own dates. Do not apply November 1, December 10, February 1 or April 10 automatically to a supplemental bill. Read the dates printed on that bill or check the live account.
2026–27 unsecured taxes: Alameda County announced a 5 p.m. August 31, 2026 deadline. The county stated that unpaid amounts after that date receive a 10% delinquent penalty plus a $50 delinquent cost, with additional monthly interest beginning later in the delinquency cycle. Use the live official balance for the amount currently required.
County guidance states that when December 10 or April 10 falls on a Saturday, Sunday or legal holiday, payment can generally be made by 5 p.m. on the next business day without the normal delinquency penalty. Verify the current bill before relying on this rule.
Pay Alameda County Property Tax by Mail or In Person
1221 Oak Street, Room 131
Oakland, CA 94612
Make checks payable to Treasurer Tax Collector, Alameda County.
1221 Oak Street, Room 131
Oakland, CA 94612
Published business hours: 8:30 a.m.–5:00 p.m. weekdays, excluding county holidays.
Mailing-date change: the Treasurer-Tax Collector warns that USPS postmark practices changed effective December 24, 2025. The county advises mailing well before a deadline or requesting a manual postmark at a post office when timing is critical.
- Use the current county mailing instructions shown on the bill or Tax Collector website.
- Include the original payment coupon when available.
- Put the parcel number or assessee account number on the payment as directed.
- Do not mail cash.
- Send payment early enough to satisfy the applicable deadline rule.
- Keep a copy of the check and mailing proof.
- Verify posting in the official account afterward.
Alameda County Property Tax Rate
There is not one single final Alameda County property-tax percentage that applies identically to every parcel. The Auditor-Controller explains that the ad valorem rate includes the 1% general tax rate plus applicable voter-approved debt service rates. Fixed charges and special assessments can also appear on a bill.
County formula for secured taxes: net assessed value × tax rate (1% plus applicable debt-service rates), plus fixed charges and/or special assessments.
2026–27 rate-book status: as of September 21, 2026, the Alameda County Auditor-Controller’s 2026–27 property-report page states that current-year composite tax-rate reports and the 2026–27 Tax Rate Book are not yet available. Do not substitute the 2025–26 rate for a parcel-specific 2026–27 rate.
- Open Alameda County’s official Tax Rate Search.
- Select the available tax year.
- Search by parcel number, property address, city/unincorporated area or Tax Rate Area.
- Use parcel-specific results rather than assuming every property in a city has the same rate.
- Review fixed charges and special assessments separately.
Alameda County Assessor Records and Parcel Lookup
The Assessor is the correct office for assessed value, property characteristics, ownership information used on the assessment roll, parcel maps, change-of-ownership questions and many exemption matters.
The APN identifies a parcel for assessment and tax purposes. It may also appear on the property-tax bill.
Use the Assessor’s property records when checking land, improvements and assessed value.
Alameda County provides a parcel viewer and assessor maps for assessment-related parcel information.
- Open the Alameda County Assessor website.
- Use the property or parcel lookup resources.
- Search using the address or APN supported by the tool.
- Confirm the exact parcel.
- Review assessed value and property characteristics.
- Check relevant exemption information.
- Use the Treasurer-Tax Collector separately for the live tax balance.
1221 Oak Street, Room 145, Oakland, CA 94612
Main phone: 510-272-3787
Public lobby hours: 9:00 a.m.–4:30 p.m., Monday–Friday except holidays.
Alameda County Property Tax Exemptions
The Assessor administers several California property-tax exemptions. Eligibility, documents and filing requirements differ by program.
Qualifying owners who own and occupy the home as their principal residence on the January 1 lien date may qualify. Alameda County estimates typical annual savings of roughly $70–$80.
Qualified disabled veterans and certain surviving spouses may qualify under California rules. The Assessor publishes eligibility and filing guidance.
Other exemptions can apply to eligible veterans, religious organizations, nonprofit organizations and other qualifying property.
| Deadline | General Meaning | Action |
|---|---|---|
| February 15 | Full-value filing deadline for several exemption programs, including the Homeowners’ Exemption. | File by this date when possible for full available exemption treatment. |
| February 16–December 10 | Homeowners’ late claims can generally receive 80% of the exemption amount. | Do not wait for the next year if a late claim is still available. |
| Program specific | Disabled-veteran, supplemental and other exemption rules can have additional deadlines. | Read the current program instructions before filing. |
- Confirm the property is your principal residence.
- Check eligibility for the relevant lien date.
- Contact the Alameda County Homeowners’ Exemption unit if you need the property-specific claim form.
- Submit the current form through the Assessor’s approved route.
- Keep filing confirmation.
- Verify the exemption appears in the assessment record.
Homeowners’ Exemption phone: 510-272-3770
Official Alameda County ExemptionsFiling cost: the Alameda County Assessor states that there is no charge to file for the Homeowners’ Exemption.
How to Appeal an Alameda County Property Assessment
If you disagree with the assessed value, first distinguish between an informal Assessor review and a formal Assessment Appeals Board filing. A tax-payment dispute and an assessment-value dispute are different processes.
| Assessment Type | Filing Period | 2026 Status |
|---|---|---|
| Regular annual assessment | July 2 through September 15 | The September 15, 2026 regular filing deadline has passed as of September 21, 2026. |
| Supplemental assessment | Generally within 60 days of the notice date or notice postmark, whichever is later. | Use the date on the individual notice. |
| Escape assessment | Generally within 60 days of the applicable notice date or postmark. | Use the individual notice and official instructions. |
You must still pay property-tax bills on time while an assessment review or appeal is pending unless official instructions specifically provide otherwise. The Assessor explicitly warns owners to continue timely payment to avoid penalties.
Alameda County Supplemental Property Tax Bills
A supplemental assessment can occur after a change in ownership or completion of new construction. Supplemental taxes are separate from the regular annual secured tax bill and can have separate due dates.
A property transfer can create a new base-year value and supplemental assessment.
Completed assessable construction can generate a supplemental assessment.
Do not substitute regular secured-tax installment dates for a supplemental bill’s printed due dates.
- Search the supplemental tax account.
- Confirm the property and assessment event.
- Review the supplemental assessment period.
- Check the bill’s individual due dates.
- Verify exemption or exclusion issues with the Assessor.
- Pay through the Treasurer-Tax Collector.
Mortgage Escrow and Duplicate Alameda County Payments
If your mortgage includes an impound or escrow account, the mortgage servicer may pay Alameda County directly. Receiving a tax bill does not automatically mean the servicer failed to pay.
- Check the Alameda County tax account for posted payment.
- Review your mortgage statement and escrow transaction history.
- Confirm whether the servicer scheduled the payment.
- Verify the correct parcel and installment.
- If the deadline is close and no payment appears, contact the servicer and Tax Collector promptly.
Duplicate-payment refunds: Alameda County’s Auditor-Controller states that duplicate property-tax payment refunds are generally issued to the party that made the second payment under the applicable California rule.
Delinquent Alameda County Property Taxes
Once taxes become delinquent, use the Treasurer-Tax Collector’s live account rather than calculating the payoff from an older bill. Penalties, costs and redemption charges can change.
The county states that a 10% penalty attaches when the first secured installment becomes delinquent.
The county states that the normal second-installment delinquency adds a 10% penalty and $10 cost.
Prior-year secured taxes can enter California’s tax-default and redemption system.
The county publishes an installment-plan process for qualifying prior-year secured property-tax delinquencies.
- Open the official prior-year tax account.
- Confirm the exact years in default.
- Request or review the current redemption amount.
- Ask whether an installment plan is still available.
- Keep current-year taxes paid while following any approved plan.
- If a tax sale is approaching, follow the Tax Collector’s current instructions immediately.
Tax-default and tax-sale issues are time-sensitive. Do not assume a payment plan is automatically available or that a general web article can determine redemption rights for a specific parcel.
Alameda County Deed and Recorded Property Records
The Clerk-Recorder handles recorded real-property documents. This is separate from the Assessor’s parcel records and the Treasurer-Tax Collector’s tax-account database.
Use for tax bills, payments, balances and delinquent-tax status.
Use for assessed value, parcel details and assessment-roll ownership information.
Use for deeds, recorded liens and other public real-property instruments.
Search-method difference: the Clerk-Recorder states that its public real-property record database is not searchable by APN or property address. Recorded-document searches use party names and document-index information.
- Open the Alameda County Clerk-Recorder real-property research page.
- Use the online public-record index for records from 1969 forward.
- Search using the owner or party name required by the index.
- Note the instrument number if you need to order a document copy.
- Do not treat the deed index as proof of the current property-tax balance.
Alameda County Property Tax Office Contacts
| Office | Contact | Use For |
|---|---|---|
| Treasurer-Tax Collector | 510-272-6800 1221 Oak Street, Room 131, Oakland, CA 94612 |
Tax bills, balances, payment, receipts, delinquent accounts. |
| Assessor | 510-272-3787 1221 Oak Street, Room 145, Oakland, CA 94612 |
Assessment, parcel data, value, ownership, property characteristics. |
| Homeowners’ Exemption Unit | 510-272-3770 | Homeowners’ Exemption filing and property-specific claim forms. |
| Assessment Appeals | 1221 Oak Street, Room 536, Oakland, CA 94612 | Formal assessment appeal applications and hearings. |
| Auditor-Controller Tax Analysis | 1221 Oak Street, Room 249, Oakland, CA 94612 | Tax rates, debt-service rates, bill corrections and tax analysis. |
| Clerk-Recorder | 510-272-6362 1106 Madison Street, Oakland, CA 94607 |
Recorded deeds, liens and other real-property documents. |
Common Alameda County Property Tax Mistakes
Assessment questions go to the Assessor; payments go to the Treasurer-Tax Collector.
Always verify payment status through the Tax Collector’s live account.
Supplemental bills carry their own payment dates.
Check for a mortgage-servicer payment before sending another payment.
An informal Assessor review does not automatically preserve formal appeal rights.
Debt rates and special charges can depend on Tax Rate Area and taxing districts.
A recorded deed or lien index does not replace the Treasurer-Tax Collector tax account.
Review the fee shown by the official payment system immediately before paying.
Official Alameda County Property Tax Resources
Alameda County Property Tax FAQs
What is the official Alameda County property tax website?
The official Alameda County property tax lookup and payment page is operated by the Treasurer-Tax Collector at alamedacountyca.gov/propertytax. Older county references may still use the acgov.org/propertytax address.
When are Alameda County secured property taxes due?
The first installment is due November 1 and becomes delinquent after 5 p.m. December 10. The second installment is due February 1 and normally becomes delinquent after 5 p.m. April 10. Weekend and legal-holiday rules can move the penalty deadline to the next business day.
How do I search an Alameda County property tax bill?
Use the official Treasurer-Tax Collector secured and supplemental tax search. The current portal supports searches by property address or parcel number. Confirm the exact property, year and installment before paying.
Does Alameda County charge an online payment fee?
The county’s current convenience-fee page states that electronic checks from checking or savings accounts have no convenience fee and lists a 2.3% convenience fee for credit-card transactions. Because another county payment page still displays 2.5%, review the fee presented by the official payment system before authorizing a card payment.
What is the Alameda County Homeowners’ Exemption?
Qualifying owners who occupy a property as their principal residence may receive a $7,000 reduction in taxable value. The Assessor estimates the typical tax savings at approximately $70–$80 per year.
When is the Alameda County assessment appeal deadline?
Regular annual assessment appeals are filed from July 2 through September 15. For 2026, that regular filing period ended September 15, 2026. Supplemental and escape assessments generally use a separate 60-day filing period tied to the assessment notice.
Can I stop paying taxes while my assessment appeal is pending?
No automatic payment suspension should be assumed. The Alameda County Assessor instructs property owners to continue paying property-tax bills on time while a review or appeal is pending to avoid penalties.
Where do I find an Alameda County deed?
Use the Alameda County Clerk-Recorder public-record system for recorded deeds and other real-property documents. The recorded-document database is separate from the Assessor parcel system and the Tax Collector account.
Bottom Line
For Alameda County property tax, use the Treasurer-Tax Collector for bills, payment and delinquent accounts; the Assessor for parcel value and exemptions; the Auditor-Controller for tax-rate questions; the Assessment Appeals Board for formal valuation appeals; and the Clerk-Recorder for deeds and recorded documents.
Official Tax Portal Tax Bill Search Assessor Tax Rates Assessment AppealsTax year/fiscal year reviewed: 2026–27 • Article reviewed: September 21, 2026 • Deadline, payment portal, fee, exemption, appeal and office information checked against current Alameda County government sources. Account-specific balances and supplemental deadlines must be verified in the live official system.