Sales tax in O'fallon, MO
The combined sales tax rate in O'fallon, MO is about 5.95%. Some local taxes in this state are not yet mapped, so the true rate may be higher.
Estimated from 6 ZIP codes covering O'fallon. Enter your ZIP code in the calculator for a closer figure.
- ZIP codes
- 6 on file, every one crossing the city line
- County
- St Charles County
Who levies sales tax across O'fallon's ZIP codes
Each government below levies its own share, but not all of them reach every address: the ZIP codes covering O'fallon 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 |
|---|---|---|---|---|---|
| Missouri | state | 4.225% | all 6 ZIP codes | Jan 1, 1993 | Missouri sales and use tax rate tables |
| St Charles County | county | 1.725% | all 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| O'fallon | city | 2% | all 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Lake St Louis | city | 2% | 4 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Cottleville | city | 2% | 3 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Dardenne Prairie | city | 2.5% | 3 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| St Peters | city | 2% | 3 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Wentzville | city | 2.5% | 3 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Josephville | city | 1% | 2 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Flint Hill | city | 1% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Foristell | city | 2% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| New Melle | city | 2% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| St Charles | city | 2% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| St Paul | city | 0% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
| Weldon Spring | city | 1.5% | 1 of 6 ZIP codes | Jul 1, 2026 | Missouri sales and use tax rate tables |
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.
ZIP codes in O'fallon
6 on file, every one crossing the city line. Each has its own page.
6 ZIP codes crossing the city line
Part of each of these lies outside O'fallon. 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 |
|---|---|---|
| 63304 | 5.95% | Cottleville, St Peters and Weldon Spring |
| 63366 | 5.95% | Dardenne Prairie, Josephville, Lake St Louis, St Paul, St Peters and Wentzville |
| 63367 | 5.95% | Dardenne Prairie, Lake St Louis and Wentzville |
| 63368 | 5.95% | Cottleville, Dardenne Prairie and Lake St Louis |
| 63376 | 5.95% | Cottleville, St Charles and St Peters |
| 63385 | 5.95% | Flint Hill, Foristell, Josephville, Lake St Louis, New Melle and Wentzville |
What can change the tax you pay in O'fallon, MO
- ZIP codes shared with a neighbour. 6 of O'fallon's 6 ZIP codes are also reached by Lake St Louis, Cottleville, Dardenne Prairie and St Peters and 8 other places, so an address in one of them can owe a neighbour's rate instead of O'fallon'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 O'fallon compares with the rest of Missouri
O'fallon's ~5.95% is below what most ZIP codes carry in Missouri. Of the state's 1,153 ZIP codes with a figure, 13 land on the same one, 80 carry a lower figure and 1,060 a higher one. Across Missouri the combined rate runs from 4.725% to 13.238%. See every city in Missouri.
| Combined rate | ZIP codes | Which is this city |
|---|---|---|
| ~6.725% | 95 | |
| ~7.225% | 72 | |
| ~6.225% | 58 | |
| ~8.725% | 44 | |
| ~8.975% | 44 | |
| ~5.95% | 13 | O'fallon |
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 5, 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.