Sunraysia Highway (route B220) is a north–south rural highway in western Victoria, linking Ouyen to the north-western Ballarat suburb of Mitchell Park, through the Parliament of Victoria provided for the establishment of the Country Roads Board (later VicRoads) and their ability to declare Main Roads, taking responsibility for the management, construction and care of the state's major roads from local municipalities. Beulah-Birchip-Wycheproof Road was declared a Main Road from Ballapur to Birchip (and continuing westwards from Ballapur to Beulah, and eastwards to Wycheproof) on 14 December 1914; and between St Arnaud and Donald on 20 September 1915; Ballarat-(Lexton-)(Avoca-)St Arnaud Road was declared a Main Road, between Addington through Lexton and Avoca to Redbank on 31 May 1915, and from north-western Ballarat to Addington and from Redbank to St Arnaud on 20 September 1915. provided for the declaration of State Highways, roads two-thirds financed by the state government through the Country Roads Board. North-Western Highway (not to be confused by Calder Highway, which was also known as North-Western Highway in the late 1920s) was declared a State Highway in the 1947/48 financial year, subsuming the original declaration of Beulah-Birchip-Wycheproof between Ballapur and Birchip as a Main Road, along the former Kinnabulla-Woomelang Road and Woomelang-Lascelles Roads.
Sunraysia Highway was signed as State Route 121 between Ouyen and Ballarat in 1986; with Victoria's conversion to the newer alphanumeric system in the late 1990s, it was replaced by route B220.
The passing of the Road Management Act 2004 granted the responsibility of overall management and development of Victoria's major arterial roads to VicRoads: in 2013, VicRoads re-declared the road as Sunraysia Highway (Arterial #6700) between Calder Highway in Ouyen and Western Freeway at Mitchell Park in north-western Ballarat.