School holidays (US “vacations”) in the British school system are usually spaced around six to seven weeks apart and are often referred to as the “school break”. Hogwarts School of Witchcraft and Wizardry, as part of the magical world, operates on a different schedule to most of the other schools in Britain:
Public (ie private) schools set their own holidays and starting dates, but state schools in the UK generally run along the following lines:
September – the start of the new school year
October – one week’s half term holiday around the third week of October
December – end of term falls just before Christmas when there is a three week break.
January – start of term around the first week of January
February – one week’s half term holiday around the second week of February
March/April – end of term two week’s break coincides with the Easter holidays and can fall before, during or after the actual date of Easter that year.
March/April – start of term (depends on Easter)
May – one week’s half term holiday the last week of May, incorporating the Late May Bank Holiday (now renamed as the Spring Bank Holiday)
July – end of term around the second week of July, although some years will end after their exams (Hogwarts School ends their term much earlier – in June).
The Lexicon's Hogwarts Timeline
From the Web
Wikipedia: Academic Year, United Kingdom