Sales tax in Unincorporated San Mateo County, CA
The combined sales tax rate in Unincorporated San Mateo County, CA is 9.375%, effective 2026-07-01.
Last verified
- ZIP codes
- 29 on file · 7 wholly inside the city limits
- Levied by
- California and Unincorporated San Mateo County
How the combined rate in Unincorporated San Mateo County, CA is made up
Each government below levies its own share. A seller collects them together at the till and passes each share to the authority that levied it.
| Jurisdiction | Type | Rate | Effective | Source |
|---|---|---|---|---|
| California | state | 7.25% | Jan 1, 2017 | California sales and use tax rates by jurisdiction |
| Unincorporated San Mateo County | city | 2.125% | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| Combined rate | 9.375% | |||
ZIP codes in Unincorporated San Mateo County
29 on file — 7 wholly inside the city limits and 22 crossing them. Each has its own page.
7 ZIP codes wholly inside Unincorporated San Mateo County
Every address in these is inside the city limits, so all of them pay Unincorporated San Mateo County's rate.
| ZIP code | Combined rate | Also reaches |
|---|---|---|
| 94018 | 9.375% | no other city |
| 94020 | 9.375% | no other city |
| 94021 | 9.375% | no other city |
| 94037 | 9.375% | no other city |
| 94038 | 9.375% | no other city |
| 94060 | 9.375% | no other city |
| 94074 | ~9.375% | no other city |
22 ZIP codes crossing the city line
Part of each of these lies outside Unincorporated San Mateo County. An address in one may be taxed at a neighbour's rate instead, and the figure shown is the most likely one across the whole ZIP code.
| ZIP code | Combined rate | Also reaches |
|---|---|---|
| 94002 | 9.875% | Belmont and Redwood City |
| 94005 | 9.875% | Brisbane |
| 94010 | 9.375% | Burlingame, Hillsborough, Millbrae, San Bruno and San Mateo |
| 94014 | 9.875% | Colma and Daly City |
| 94015 | 9.875% | Daly City |
| 94019 | 9.875% | Half Moon Bay |
| 94025 | 9.375% | Menlo Park |
| 94027 | 9.375% | Atherton |
| 94028 | 9.375% | Menlo Park, Palo Alto, Portola Valley and Unincorporated Santa Clara County |
| 94030 | 9.375% | Millbrae and San Bruno |
| 94044 | 9.875% | Pacifica and San Bruno |
| 94061 | 9.875% | Redwood City and Woodside |
| 94062 | 9.375% | Redwood City and Woodside |
| 94063 | 9.875% | Redwood City |
| 94066 | 9.875% | San Bruno and South San Francisco |
| 94070 | 9.375% | Belmont, Redwood City and San Carlos |
| 94080 | 9.875% | Colma, San Bruno and South San Francisco |
| 94128 | 9.875% | South San Francisco |
| 94303 | 9.75% | East Palo Alto, Menlo Park, Mountain View, Palo Alto and Unincorporated Santa Clara County |
| 94402 | 9.625% | San Mateo |
| 94403 | 9.625% | San Mateo |
| 94404 | 9.375% | Foster City and San Mateo |
What can change the tax you pay in Unincorporated San Mateo County, CA
- ZIP codes shared with a neighbour. 22 of Unincorporated San Mateo County's 29 ZIP codes are also reached by Redwood City, San Bruno, San Mateo and Menlo Park and 19 other places, so an address in one of them can owe a neighbour's rate instead of Unincorporated San Mateo County's.
- What you are buying. Categories are not taxed alike. The calculator switches between general merchandise, prepared food and lodging, which are the categories we hold rates for here.
How Unincorporated San Mateo County compares with the rest of California
Unincorporated San Mateo County's 9.375% is above what most ZIP codes carry in California. Of the state's 2,584 ZIP codes with a figure, 17 land on the same one, 1,782 carry a lower figure and 785 a higher one. Across California the combined rate runs from 7.25% to 11.25%. See every city in California.
| Combined rate | ZIP codes | Which is this city |
|---|---|---|
| ~7.75% | 535 | |
| ~8.75% | 373 | |
| ~9.75% | 346 | |
| ~7.25% | 282 | |
| ~8.25% | 189 | |
| ~9.375% | 17 | Unincorporated San Mateo County |
Counted from ZIP-code figures. A tilde marks a band where some ZIP codes cross a tax boundary and are counted at their most likely rate.
How sales tax is collected
The seller generally collects the tax from the buyer at the point of sale and passes it to the authorities that levied it. In most states it is added at the till rather than included in the advertised price. Read how sales tax works, including sourcing rules, online purchases and who is required to collect.
Rates last verified: Sep 4, 2026. This is when the source was last read, not when this page was last edited.
TaxAndTips provides informational estimates from published tax-rate data. Actual tax treatment can depend on the product or service, the exact address, the transaction, exemption status and applicable law. For official obligations, consult the taxing authority or a qualified tax professional.
Why you can rely on these figures
- Published rates
- State and local rates compiled from the tax authorities that levy them.
- Every figure sourced
- See the jurisdiction breakdown and the document each rate came from.
- No signup
- Use the calculator immediately. Nothing to create, nothing to install.
- Missing means missing
- Where a rate is not verified we say so instead of showing a short total.