We all agree that it would be much easier if the tax year started on the 1st of January and ended on the 31st of December, so why isn't it that way?
- 25 MarchLady Day, the old New Year's Day, until 1752
- 5 AprilFrom 1753, 11 days later, for the days skipped in 1752
- 6 AprilFrom 1800, one more day later, because 1800 wasn't a leap year under the new calendar
The truth is that the 6th April start has more to do with long-standing British tradition than convenience.
In England, major Christian holidays would serve as days for settling rents and debts. The first of these days, "Lady Day", commemorated the angel Gabriel's announcement to Mary and so this used to mark New Year's Day.
Back then, New Year's Day wasn't the 1st of January, it was the 25th of March – sounds absurd, right?
Since the 25th of March was the start of the calendar year, it was also chosen as the start of the tax year.
The calendar change
For a long time, much of the world used the Julian Calendar (named after Julius Caesar), which wasn't entirely accurate, causing a problem for Christian churches in calculating the day of Easter, and in 1582 Pope Gregory XIII (the head of the Catholic Church) sought to fix this.
The Gregorian Calendar was commissioned and that year, the 4th of October was followed by the 15th of October, rather than the 5th.
This was to correct the 10 day mismatch that had accumulated over centuries of using a calendar whose year was about 11 minutes longer than the time the Earth takes to go round the Sun.
Many countries complied with the new calendar straight away, but Britain didn't. As Protestants, they had 'beef' with the Catholics and didn't adopt the calendar until 1752.
When they finally did adopt the Gregorian Calendar, the mismatch had grown to 11 days, so they had to follow the 2nd of September in 1752 with the 14th of September. They were now in sync with everyone else.
| Mon | Tue | Wed | Thu | Fri | Sat | Sun |
|---|---|---|---|---|---|---|
| 1 | 2 | 14 | 15 | 16 | 17 | |
| 18 | 19 | 20 | 21 | 22 | 23 | 24 |
| 25 | 26 | 27 | 28 | 29 | 30 |
Wednesday the 2nd was followed by Thursday the 14th. The 3rd to the 13th never happened.
But the tax man didn't want to miss out on 11 precious days of tax revenue, so the tax year moved 11 days forward too, now starting on the 5th of April.
Later in 1800, a year which would have been a leap year under the old Julian Calendar – but wasn't under the new Gregorian one – the Treasury moved the start of the tax year again, this time to the 6th of April.
So here we are!
This guide gives general information only.
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