100 Mile House is a district municipality located in the South Cariboo region of central British Columbia, Canada.

Its origins as a settlement go back to the time when Thomas Miller owned a collection of ramshackle buildings serving the traffic of the gold rush as a resting point for travellers moving between Kamloops and Fort Alexandria, which was 158 kilometres (98 mi) north of 100 Mile House farther along the Hudson's Bay Brigade Trail.

[6]: 198 In 1930, Lord Martin Cecil left England to come to 100 Mile House and manage the estate owned by his father, the 5th Marquess of Exeter.

The estate's train stop on the Pacific Great Eastern (now BC Rail leased and operated by Canadian National) railway is to the west of town and called Exeter.

Today, the town is served by the 100 Mile House Regional Transit System and by Adventure Charters intercity bus service four times a week in each direction.

In spite of the moderation that comes from its relative proximity to the Pacific Ocean, extreme winter temperatures can occasionally occur, with a record low of −48 °C (−54 °F).

100 Mile House is located in a rain shadow of the coastal mountains, resulting in reduced precipitation, much of it falling as snow.