Whitsun is the name used in Britain, and other countries among Anglicans and Methodists, for the Christian holy day of Pentecost. It falls on the seventh Sunday after Easter and commemorates the descent of the Holy Spirit upon Christ's disciples. In England it took on some characteristics of Beltane, which originated from the pagan celebration of Summer's Day, the beginning of the summer half-year, in Europe. Whitsuntide, the week following Whitsunday, was one of three holiday weeks for the medieval villein; on most manors he was free from service on the lord's demesne this week, which marked a pause in the agricultural year. Whit Monday, the day after Whitsun, remained a holiday in Britain until 1971 when, with effect from 1972, the ruling Conservative Government decided to permanently replace it, following a five year trial period, with a Spring Bank Holiday on the last Monday in May. Whit had been the occasion for many varied forms of celebration, and was of significant cultural importance. It was a custom for children to receive a new set of clothes, even among the poorest families, a tradition which continued well into the 20th century.

Whit Friday, meaning "white Friday", is the name given to the first Friday after Pentecost or Whitsun.