By car is the only practical way in, there is no air or rail service and limited bus services.
Interstate 90 (I-90) passes by at the south side of town. Ellensburg is accessed from Exit #106 (W. University Way & Thorp Hwy) and 109 (Canyon Rd). Located 110mi/165km (1hr38min) east of Seattle and 170mi/272km (2hr44min) west of Spokane.
Interstate 82 (I-82) begins southeast of Ellensburg at Exit 110. I-82 goes southeast through Yakima (36mi/57.5km), Toppenish, Sunnyside, Tri-Cities (113mi/181km) and down into Hermiston, Oregon (142mi/227km). Ends at the junction with Interstate 84. From I-84, I-82 starts from Exit #179.
US-Hwy 97 goes another 160mi/256km (3hr) north to Omak and another 48mi/77km (:45min) from Omak to Osoyoos, BC by Lake Osoyoos, just over the U.S./Canadian border. From I-90, access to US Hwy 97 northbound is off of Exit #106 and the first left (north) from the eastside of the freeway. Going southbound, US-97 follows I-82 to Union Gap just south Yakima where it branches off again on a separate road to Toppenish and south to Biggs Junction, Oregon (Exit #104 along Interstate 84 in Oregon).
Greyhound has four departures daily to Seattle from a stop at the western edge of town (see below):
Greyhound, Love's Truck Stop @ 1512 Hwy 97 (off of Exit 106 from I-90), ☎ 509-925-1177 (toll free: 1-800-231-2222), . Travels primarily on Interstate 90 (Seattle, Ellensburg, Moses Lake, Spokane, Couer d'Alene, Kellog, St Regis & Missoula), 82 (Stanfield, OR; Pasco, Sunnyside, Yakima, Ellensburg & Seattle) and US395 (Pasco-Ritzville-Spokane). Passengers transfer to other buses in Seattle, Spokane, Stanfield or Missoula to get to additional cities.edit
Besides Greyhound there are:
Northwestern Trailways, Love's Truck Stop @ 1512 Hwy 97 (off of Exit 106, same stop as Greyhound), ☎ 509-838-4029 (toll free: 1-800-366-3830), . operates the state's "Travel Washington Apple Line" bus  between Ellensburg, Wenatchee & Omak.edit
Bellair Airporter, Quality Inn @ 1700 Canyon Rd S (2 blocks north on Canyon Rd from exit 109), ☎ 360-380-8880 (toll free: 866-235-5247), . Goes west to Cle Elum, North Bend and SeaTac Airport and southeast to Yakima. Can make an additional stop at CWU (Central Washington University) Starbucks at 908 E 10th St (in town) by reservation ONLY, does not automatically stop there.edit
Ellensburg Commuter (Yakima Transit Rt #11 & by Hopesource) goes up to Ellensburg & Central Washington University (CWU) campus four times daily from Yakima.
By car is the most practical & convenient way around town and around Kittitas County. There is NO rail service and very limited bus services in the county. If necessary, Hopesource operates shuttle buses to Cle Elum 3x daily, continue to Easton on request only on one route and to Yakima on the Yakima Commuter on another route. Locally 'Central Transit' provides in town shuttles. .