Sales tax in Diamond Bar, CA
The combined sales tax rate in Diamond Bar, CA is about 9.75%, and ranges from 9.75% to 10.5% depending on the exact address.
Estimated from 3 ZIP codes covering Diamond Bar. Enter your ZIP code in the calculator for a closer figure.
- ZIP codes
- 3 on file, every one crossing the city line
- County
- Los Angeles County
ZIP codes in Diamond Bar
3 on file, every one crossing the city line. Each has its own page.
3 ZIP codes crossing the city line
Part of each of these lies outside Diamond Bar. 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 |
|---|---|---|
| 91765 | 9.75% | Pomona and Unincorporated Los Angeles County |
| 91768 | 10.5% | Pomona and Unincorporated Los Angeles County |
| 91789 | 9.75% | Industry, Pomona, Unincorporated Los Angeles County, Walnut and West Covina |
Who levies sales tax across Diamond Bar's ZIP codes
Each government below levies its own share, but not all of them reach every address: the ZIP codes covering Diamond Bar reach into more than one city, and an address pays only the shares whose boundary it falls inside.
| Jurisdiction | Type | Rate | Applies to | Effective | Source |
|---|---|---|---|---|---|
| California | state | 7.25% | all 3 ZIP codes | Jan 1, 2017 | California sales and use tax rates by jurisdiction |
| Diamond Bar | city | 2.5% | all 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| Pomona | city | 3.25% | all 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| Unincorporated Los Angeles County | city | 2.5% | all 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| Industry | city | 2.5% | 1 of 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| Walnut | city | 2.5% | 1 of 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
| West Covina | city | 2.5% | 1 of 3 ZIP codes | Jul 1, 2026 | California sales and use tax rates by jurisdiction |
No total is shown because more than one city is listed. An address falls inside only one of each, so these shares are alternatives rather than a stack, and adding them all up would give a figure nobody pays.
What can change the tax you pay in Diamond Bar, CA
- ZIP codes shared with a neighbour. 3 of Diamond Bar's 3 ZIP codes are also reached by Pomona, Unincorporated Los Angeles County, Industry and Walnut and 1 other place, so an address in one of them can owe a neighbour's rate instead of Diamond Bar'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 Diamond Bar compares with the rest of California
Diamond Bar's ~9.75% is above what most ZIP codes carry in California. Of the state's 2,584 ZIP codes with a figure, 346 land on the same one, 1,825 carry a lower figure and 413 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 | Diamond Bar |
| ~7.25% | 282 | |
| ~8.25% | 189 |
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.