California IFTA Filing Walkthrough (Quarterly)

California runs IFTA through the Department of Tax and Fee Administration, and everything, from the first license application to every quarterly return, happens in the CDTFA online services portal. The sourced fee and rule facts live on the California IFTA page; this walkthrough puts them in filing order.

Step 1: confirm you need a California IFTA license

You qualify for (and need) a California IFTA license when you run a qualified motor vehicle from a California base into at least one other IFTA jurisdiction. California's base-jurisdiction test asks for a vehicle registered with the California DMV, an established physical place of business in the state (a PO box does not qualify), and operational control and records kept in California. A carrier that only crosses between California and Mexico can use the Interstate User Diesel Fuel Tax License instead, and a carrier that rarely leaves the state can weigh single trips on the trip and fuel permits instead of a license.

Step 2: register through CDTFA online services

Apply in the CDTFA online services portal. The application asks for vehicle information, your social security number or FEIN, your driver license number, and your DOT number. The annual license fee and the per-set decal fee are small and render with sources on the California IFTA page; one decal set goes on each qualified vehicle.

Step 3: keep miles and gallons by jurisdiction

Every quarter's return is built from two running totals per jurisdiction: miles traveled and gallons purchased. ELD or GPS mileage plus fuel receipts is the standard record set. Sloppy quarter-end reconstructions are the single most common cause of IFTA audit pain, which the how to file IFTA guide covers in depth.

Step 4: file the quarterly return in the portal

California IFTA returns are due quarterly, on the last day of the month following the reporting period, filed through the same CDTFA online portal. The return applies each jurisdiction's current rate to your miles and gallons; California's own diesel line this quarter is $0.9710IFTA Fuel Tax Rate Matrix, 3rd Quarter 2026 (International Fuel Tax Association, Inc. (IFTA, Inc.))Verified Jul 18, 2026 per gallon in the national matrix. Run your quarter through the IFTA calculator before filing to sanity-check the balance, and check any jurisdiction's line on the IFTA rates by state table. File even for quarters with zero travel.

Step 5: renew before the grace period ends

California renewal opens in December for the following license year, and prior-year decals ride a grace period through the last day of February. Renewing inside that window keeps trucks legal while new decals arrive.

FAQ

Who administers IFTA for California carriers?

The California Department of Tax and Fee Administration. Registration and quarterly returns both run through the CDTFA online services portal, and the license and per-set decal fees render with sources on the California IFTA page.

When are California IFTA returns due?

Quarterly, on the last day of the month following the reporting period. A return is due even for quarters with no travel.

Is there a California alternative to IFTA for Mexico-only routes?

Yes. Carriers operating only between Mexico and California can use the Interstate User Diesel Fuel Tax License instead of an IFTA license.