TITLE: US Sales Tax Changes: 1 October 2026 Updates for California, Texas and Pennsylvania
If you sell into the United States from the UK, Europe, Canada, Australia or another country, 1 October 2026 is a critical systems date. California, Texas and Pennsylvania all introduce sales tax changes on the same day.
The District of Columbia does not introduce the widely reported general rate increase on 1 October. Its 6% general rate remains in place until 30 September 2027.
You should update your tax engine, validate delivery addresses and review your economic nexus position before the changes take effect. Doing this now will reduce under-collection, filing corrections and customer disputes.
Understand the US sales tax structure before you update your system
US sales tax is state and local. It is not a federal tax administered by the IRS.
States establish the main rules. Counties, cities and special purpose districts may add local taxes. Each jurisdiction can also set its own registration, economic nexus and filing requirements.
This means your business may need to:
- Monitor sales into multiple states.
- Register after crossing an economic nexus threshold.
- Apply the correct tax to each ship-to address.
- Separate state and local tax in your records.
- File returns through the relevant state authority.
- Reconcile marketplace, website and fulfilment-centre data.
For international sellers, including Amazon sellers and digital businesses, using one national US tax rate is not sufficient. Your system must calculate tax based on the applicable jurisdiction and transaction details.
Pennsylvania: switch Philadelphia and Allegheny County to destination sourcing
Pennsylvania’s Act 21 of 2026 changes how local sales tax is sourced in Philadelphia and Allegheny County.
The Pennsylvania Department of Revenue guidance confirms that the change was enacted on 12 July 2026. It applies retroactively for tax years beginning after 31 December 2025, but enforcement starts on 1 October 2026.
Previously, local tax was generally linked to the vendor’s location. Under the new rule, local tax follows the delivery destination.
Apply the correct Pennsylvania rate
If you are already required to collect Pennsylvania’s 6% state sales tax, you must also collect the relevant local tax on taxable deliveries to:
- Philadelphia: 6% state tax plus 2% local tax, producing an 8% combined rate.
- Allegheny County, including Pittsburgh: 6% state tax plus 1% local tax, producing a 7% combined rate.
Pennsylvania’s economic nexus threshold remains $100,000 of annual Pennsylvania sales.
If you crossed that threshold and collected only 6% on all Pennsylvania transactions, you may have technically under-collected on deliveries into Philadelphia and Allegheny County from 1 January 2026 onwards.
Do not make unsupported retrospective adjustments. The Department of Revenue has provided an enforcement transition period. Update your system for 1 October, document your treatment of the January–September period and confirm the correct filing position with the Department before amending returns. The Department’s published contact number is 717-787-1064.
Pennsylvania uses centralised filing through Form PA-1, which captures state and local tax separately. Review your return mapping so local collections are not incorrectly reported as state tax.
California: update both the rate and tax code
California’s CDTFA Publication L-1037 introduces new sales and use tax rates effective 1 October 2026.
The most significant change is in Los Angeles County:
- Current countywide rate: 9.750%.
- New countywide rate: 10.250%.
- Current tax code: B47.
- New tax code: D29.
The 0.500% increase applies countywide. City rates within Los Angeles County also increase where the countywide change applies. CDTFA Publication L-1037 lists additional city and district-level changes, including new codes for affected locations.
Do not update only the percentage
Your tax engine must update both:
- The tax rate percentage.
- The applicable California district tax code.
Changing only the percentage can create incorrect reporting, even when the amount charged appears correct. Tax codes help determine where the tax is allocated and how it must be reported.
CDTFA address-level lookups for the new rates go live on 1 October 2026. Test your tax engine using delivery addresses in Los Angeles County and other affected California districts. Keep evidence of the rate tables and system changes used for your October filings.
Texas: refresh address-level local tax logic
Texas has a 6.25% state sales tax rate. Local jurisdictions can add tax, producing a maximum combined rate of 8.25%.
Texas is destination-based for remote sellers. You must therefore apply local tax using the customer’s ship-to address, not your warehouse, office or marketplace location.
The Texas Comptroller’s October 2026 update lists the following changes effective 1 October:
Cities and counties adopting or increasing local tax
- Beckville, Panola County: total rate of 8.25%.
- Ellinger: total rate of 8.25%.
- Frost: total rate of 8.25%.
- Northlake, Denton County: total rate of 8.25%.
- Fayette County: additional 0.5% county rate.
- Navarro County: additional 0.5% county rate.
Northlake also has changes involving its city and development district tax purposes. Your tax engine should use the address-specific jurisdiction result rather than applying a manual city-wide assumption.
Cities abolishing local taxes
The update also identifies local tax changes for:
- Bellmead, reducing the total rate to 8.0%.
- Naples, reducing the total rate to 8.0%.
- Orchard, reducing the total rate to 8.0%.
- Roscoe, reducing the total rate to 8.0%.
- Shoreacres, reducing the total rate to 6.25% following its merger with La Porte.
The La Porte and Shoreacres merger takes effect on 1 October 2026. Shoreacres abolishes its sales tax as part of the change.
Special purpose districts require extra testing
New or changed special purpose district taxes include:
- Ellis County Emergency Services District No. 1: 2.0%.
- Ellis County Emergency Services District No. 9: 2.0%.
- Ellis County Emergency Services District No. 9-A: 1.5%.
- Kaufman County Emergency Services District No. 1: 2.0%.
- Kaufman County Emergency Services District No. 1-A: 1.75%.
- Montgomery County Emergency Services District No. 10: 1.0%.
- Montgomery County Emergency Services District No. 10-A: 2.0%.
- Northlake Municipal Development District: 0.5%.
These districts may cover only parts of a county or certain ZIP codes. Validate the full address and boundary result. ZIP code alone may not be reliable enough for a complex Texas location.
D.C. update: no general rate increase on 1 October
The District of Columbia is not introducing the widely reported general sales tax rate increase on 1 October 2026.
D.C.’s 6% general sales tax rate remains in place until 30 September 2027.
Do not change your D.C. rate logic in response to the 1 October changes in California, Texas and Pennsylvania. Applying an incorrect general rate increase to D.C. transactions would create over-collection and potential customer disputes.
If your tax engine is configured to apply a nationwide or multi-state rate update on 1 October, confirm that D.C. is explicitly excluded from that update.
Build your 1 October 2026 checklist
These changes affect different parts of your tax calculation. Work through each item before the effective date:
- Pennsylvania: Switch Philadelphia and Allegheny County to destination sourcing. Apply the 8% and 7% combined rates to taxable deliveries into those areas.
- California: Update the Los Angeles County rate to 10.250% and change the tax code from B47 to D29. Review all other city and district-level changes in CDTFA Publication L-1037.
- Texas: Refresh address-level local tax logic for the adopting, increasing and abolishing cities, counties and special purpose districts.
- District of Columbia: Confirm no general rate change is applied. The 6% rate remains until 30 September 2027.
- Economic nexus: Review your nexus position for each state. Pennsylvania’s threshold remains $100,000 of annual Pennsylvania sales.
- Return mapping: Confirm your Pennsylvania filing through Form PA-1 captures state and local tax separately, and that California district tax codes are mapped correctly.
- Test data: Use delivery addresses in Los Angeles County, Philadelphia, Allegheny County and affected Texas jurisdictions to test your tax engine before 1 October.
Document the rate tables, codes and system changes used for your October filings. Keeping this evidence will help if a filing position is later questioned.