Murtho is a locality in South Australia. It is northeast of Renmark and Paringa. It is bounded by the Murray River on its north and west sides and the Victorian border on the east.
Land around Murtho today is used for vineyards and orchards irrigated from the Murray River, and cereal crops. It has a boat ramp and shop which supports campers and recreational fishing.
A village settlement was established at Murtho, 2–3 miles (3–5 km) upstream of Renmark (on the opposite bank) in the 1890s as a socialist colony. The Village Settlements established under Part VII of the Crown Lands Amendment Act 1893 was mostly used by unemployed people seeking a fresh start during an economic depression. Murtho was different in that it required financial commitment by the members and no government handouts. Chairman of the Murtho Co-operative Village Settlement Association was Henry Cordeaux ( –1902). By 1897, Murtho had 60–70 acres (24–28 ha) under irrigation. However, by 1899, Murtho settlement had, like many others, been largely abandoned. The settlement failed chiefly through inadequate irrigation — the settlement was atop a 120 feet (37 m) cliff. This was initially seen as an advantage, as the land sloped away from the banks, thus easier to irrigate but the double-acting plunger pump required to raise water to this height was expensive, inefficient, and could barely cope with 20 feet (6.1 m) of suction lift during "normal" low river levels, and failed utterly when the river dropped further. The cost of transporting provisions and produce by river was exorbitant (dearer per ton than from London to Adelaide), and rabbits took much of their crop: they bypassed the wire netting fences by scaling the cliffs! Among the Murtho settlers were brothers John Napier Birks (1845–1929) and Walter Richard Birks (1847–1900), of Adelaide's prominent Birks family.