As the gas tax bill makes its way through the California Legislature, here are three things you need to know:

1. Most drivers will see a $25 or $50 transportation improvement fee

Almost 90 percent of vehicles registered statewide are valued at $24,999 or less, meaning drivers will pay either the $25 or $50 transportation improvement fee. If passed, this fee -- based on the sliding scale below -- takes effect Jan. 1, 2018. It would be paid along with your vehicle registration. 

2. The transportation improvement fee is tax-deductible.

Save those receipts! The new transportation improvement fee would be tax-deductible, just like the vehicle license fee you now pay as part of your vehicle registration fee. You can calculate what your vehicle license fee would be on the state DMV's website here

3. The gas tax is going to increase, even if the bill does not pass. 

The current excise tax is 27.8 cents per gallon. Come July 1, it'll be 29.7 cents per gallon. The state's Board of Equalization is mandated annually to adjust the gas tax so this change takes effect even if the gas tax bill does not pass. 

Beyond July's increase, if the bill passes, the gas tax would be 41.7 cents per gallon starting Nov. 1.