The Royal Burgh of Haddington is a town in East Lothian, Scotland. It is the main administrative, cultural and geographical centre for East Lothian. It lies about 17 miles east of Edinburgh. The name Haddington is Anglo-Saxon, dating from the sixth or seventh century AD when the area was incorporated into the kingdom of Bernicia. The town, like the rest of the Lothian region, was ceded by King Edgar of England and became part of Scotland in the tenth century. Haddington received Burgh status, one of the earliest to do so, during the reign of David I (1124–1153), giving it trading rights which encouraged its growth into a market town.

A royal burgh was a type of Scottish burgh which had been founded by, or subsequently granted, a royal charter. Although abolished by law in 1975, the term is still used by many former royal burghs.