Most of the world quite sensibly uses 1 January to be the start of their tax year. The UK, ever keen to be different, uses 6 April. So why does the tax year run from 6 April?

For over 1600 years, the UK used the Julian calendar, named after Julius Caesar. However, the Julian calendar did not accurately correlate with the actual time taken for the earth to travel around the sun (the solar year), and was approximately 11½ minutes out per year. By the late 1500s, the Julian calendar was behind by approximately 10 days.

In 1582, Pope Gregory XIII ordered a change from the Julian calendar to the Gregorian calendar. The Gregorian calendar introduced a leap year system to combat the differences with the Solar year. Whilst most of Europe adopted the Gregorian calendar, due to England’s conflict with the Roman Catholic Church, England initially refused to make the change and carried on with the Julian calendar. It was some 170 years later when England decided to change to the Gregorian calendar. By this point, England was 11 days out of alignment with most of the rest of Europe.

In order to catch up the missing days, 11 days were skipped in September 1752, meaning that the calendar went straight from 2 September to 14 September. In England at that time, the New Year started on 25 March, also known as “Lady Day”, commemorating the Angel Gabriel bringing the news to the Virgin Mary of her pregnancy. The Treasury, concerned about losing out on 11 days revenue, decided that the tax year in 1753, which ordinarily would have begun on 25 March, would instead begin on 5 April.

In 1800, the Treasury were again concerned about lost revenue due to leap years. The Treasury therefore declared that 1800 would be a leap year for the tax year but not for the purposes of the calendar year. The start of the tax year was therefore moved from 5 April to 6 April. Whilst in 2001 Ireland changed the start of their tax year from 6 April to 1 January, the UK has doggedly kept with April 6 as the start of their tax year ever since.

Did you know the quirk leading to the tax year beginning on 6 April? Would you find it easier if the tax year began on 1 January?