List of highway route numbers in Oregon Mainline routes Mainline routes

| Number_ | South_west_end | North_east_end | Formed | Eliminated_ |
|---|---|---|---|---|
| Oregon Route 22 | US 101 at Hebo | US 20 west of Suttle Lake | 1932 |  |
| Oregon Route 23 | US 97 at Cow Canyon | US 30 in The Dalles | 1932 | 1952 |
| Oregon Route 26 | US 101 in Newport | OR 99E in Albany | 1932 | 1943 |
| Oregon Route 27 | US 20 west of Brothers | US 26 in Prineville | 1932 |  |
| Oregon Route 31 | US 395 at Valley Falls | US 97 south of La Pine | 1932 |  |
| Oregon Route 32 | US 730 east of Umatilla | US 30 near Stanfield | 1945 | 1973 |
| Oregon Route 34 | US 101 in Waldport | US 20 in Lebanon | 1932 |  |
| Oregon Route 35 | US 26 east of Government Camp | I-84/US 30 west of Hood River | 1932 |  |