You should fuel in Oregon as often as possible. When you fuel in other states you are essentially making an interest free loan to the government until you settle up at the end of the quarter.
If you buy all your fuel in Oregon, you still owe the same amount to IFTA at the end of the quarter,but at least the MF'ers aren't using your money interest free for three months.
It depends on the states you fuel and the states you travel in. On my last two quarters, I ended up owing IFTA money. So, they were the ones giving me an interest-free loan. If you drive in only two states, and you fuel mostly in the state with a lower fuel tax, you will owe IFTA money, therefore, receiving an interest-free loan.
That is nothing compared to the toll rates on the northeast. California doesn’t have many tolls. The San Francisco area is like the only region with actual unavoidable tolls. Most of California can be traveled without any tolls, especially south of San Francisco.
There is a trend of toll roads going on throughout the US. It’s happening in a lot of states, but most of the new ones appear to be optional or traveling next to toll-free roads as we see in Dallas-Fort Worth, Atlanta, etc.
I'm in Oregon every week and always fill up there. Even with the monthly use tax, the savings is huge at the pump. Most of the time it's at least a buck cheaper per gallon than California, and .50 to .75 cheaper than Washington.