The fee for testing is $25. This is added to whatever fees are printed on your registration renewal letter. https://www.oregon.gov/odot/dmv/pages/fees/vehicle.aspx Also, new Multnomah County fees: https://content.govdelivery.com/accounts/ORDOT/bulletins/2a92048#:~:text=For%20registrations%20expiring%20in%20January,%2478%20each%20two-year%20renewal.
They vary depending on the age of the vehicle, what county you live in, and the vehicle's gas mileage. Go to Oregon.gov dept of motor vehicles to find the rates
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