Iceland has a shrinking network of long-distance bus routes, with services provided by a handful of main companies. The free Public Transport in Iceland map has an overview of routes; pick it up at tourist offices or view it online at www.publictransport.is.
From roughly June to August, regular scheduled buses run to most places on the Ring Road, into the popular hiking areas of the Southwest, and to larger towns in the Westfjords and Eastfjords, and on the Reykjanes and Snæfellsnes Peninsulas. The rest of the year, services range from daily, to a few weekly, to nonexistent.
In summer 2018, there was no service linking Egilsstaðir in the east with Höfn in the Southeast, making it nearly impossible to complete the Ring Road by bus.
In summer, 4WD buses run along some F roads (mountain roads), including the highland Kjölur, Sprengisandur and Askja routes (inaccessible to 2WD cars).
Many bus services can be used as day tours: buses spend a few hours at the final destination before returning to the departure point, and may stop for a half-hour at various tourist destinations en route.
Bus companies may operate from different terminals or pick-up points. Reykjavík has several bus terminals; in small towns, buses usually stop at the main petrol station or camping ground, but it pays to double-check.
Many buses are equipped with free wi-fi.
Many buses have GPS tracking, so you can see when your bus is approaching your stop.
Main bus companies:
Reykjavík Excursions Departs from BSÍ Bus Terminal in Reykjavík.
SBA-Norðurleið Departs from BSÍ Bus Terminal in Reykjavík.
Sterna Departs from Harpa in Reykjavík; stops at Reykjavík Campsite.
Strætó Main terminal for long-distance buses is at Mjódd.
Trex Hiker transport; has a few departure points in Reykjavík (including the main tourist office and Reykjavík Campsite).