This is a steady I‑5 drive with a simple rule: leave before late morning or wait for the evening. The route and distance stay the same all day, so the gap between the fastest start and the 3:00 PM peak, 48 minutes, is all traffic. A late start is the fastest of all: 9:00 PM beats even dawn.
When to leave
Starts from 5:00 to 9:00 AM all come in under three hours. The slowdown builds from midday and peaks between 2:00 and 4:00 PM. After 6:00 PM it eases quickly, which makes an after-work departure an easy way to reach Portland with time left for dinner.
Other ways to go
Amtrak Cascades runs six round trips a day, plus the Coast Starlight, and takes about three and a half hours along Puget Sound. That is a little slower than the best drive, but you can read, work and skip Portland parking. In August 2026, buses replaced trains for a few weeks after a fire near Portland Union Station; full service returned on August 19-20.
FlixBus runs the corridor several times a day and is usually the cheapest option. Alaska and Delta fly SEA-PDX in under an hour, but for a downtown-to-downtown trip the airports add more time than the flight saves.
Parking in Portland
Portland's SmartPark garages are open around the clock. The first hour costs $2.35, all-day parking is $13 to $18 and weekend days are $7. Street meters cost $3.20 an hour and are enforced 8:00 AM-7:00 PM Monday to Saturday and 1:00-7:00 PM on Sunday; pay with the Parking Kitty app. On Timbers or Thorns game days, meters around Providence Park go up to $7.40 an hour.
On the road
There is still no toll on the Interstate Bridge over the Columbia; tolling is now set to begin on July 1, 2028. In heavy winter rain, keep an eye on the stretch near Chehalis, where flooding closed 20 miles of I‑5 in January 2022. WSDOT's travel map shows current closures.
Planning another trip? Read Chicago to Milwaukee.
