As of February 2019, it's exactly $21, but you only pay if your vehicle passes the test. No charge if it fails. Some vehicles are exempt and don't need to be tested, either because of your home address or year the vehicle was manufactured. Here's a link to the states website showing the current price. https://www.oregon.gov/deq/Vehicle-Inspection/Pages/Portland-Area-Stations.aspx And here's a link to see if your vehicle is exempt from testing. https://www.oregon.gov/deq/Vehicle-Inspection/Pages/Portland-Required-to-Test.aspx Side note. I personally received a letter saying I had to pay for testing. It was wrong. I had a newer vehicle and live outside the testing zone. So I told them and then I didn't have to pay the $21 fee. Always check for yourself before going in. Good luck!
I believe its $21 if you passed, if you didn't passed you don't pay.
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