OR 140 continues east of here, on an alignment known either as the South Klamath Falls Highway No. 424 or the Southside Bypass. Southeast of town, OR 140 intersects with Oregon Route 39, heads north on a shared alignment for about two miles, on the Klamath Falls-Malin Highway No. 50, and then continues east towards Lakeview on the Klamath Falls-Lakeview Highway No. 20.
In Lakeview, the highway intersects with U.S. Route 395 over the Fremont Highway No. 19 and then continues east on the Warner Highway No. 431 eventually dropping down into Nevada. Oregon Route 140 ends at the Nevada state line, where it becomes State Route 140.
| County | Location | Milepoint | Destinations | Notes |
|---|---|---|---|---|
| Jackson | 270 0.00 | |||
| Klamath | 270 43.58 | Westside Road – Rocky Point, Fort Klamath, Crater Lake National Park | Former Klamath Lake Highway | |
| Klamath Falls | 270 68.76 21 58.86 | West end of OR 66 overlap | ||
| 21 59.05 424 0.00 | , Weed | East end of OR 66 overlap | ||
| 424 1.57 | Tingley Lane (Midland Highway) | |||
| 424 2.80 | Washburn Way | Interchange; signed as exit 3 | ||
| 424 5.97 50 1.78 | , Alturas | West end of OR 39 overlap | ||
| 50 0.00 20 5.54 | East end of OR 39 overlap | |||
| Dairy | 20 19.02 | |||
| Lake | Lakeview | 20 96.37 19 143.03 | – Alturas, Reno | West end of US 395 overlap |
| 19 138.34 431 0.00 | East end of US 395 overlap | |||
| Adel | 431 28.18 | Plush-Adel Road, Twenty Mile Road – Plush, Hart Mountain Refuge, Fort Bidwell, Coleman Valley | Former Warner Highway (north to Plush) | |
| Harney | 431 65.28 | Nevada state line | ||