Why does the UK tax year run from April to April?
The new UK tax year is coming! But why does it run from 6th April – why not January to January?
Well, it all started a very long time ago when – in England and Ireland – the New Year started on 25th March. It was known as Lady Day to commemorate the angel Gabriel’s happy news to the Virgin Mary, that she would soon give birth to Jesus Christ.
Why the shift from 25th March to 6th April?
Hundreds of years ago, people were using a calendar proposed by Julias Ceasar in 46 BC –aptly named the Julian calendar. It’s the calendar we all know and love today: ‘30 days has September, April, June and November…’ you know the rest.
But the Julian calendar was 11 ½ minutes longer than the solar year. And over time those minutes really started to add up… By 1582 the Julian calendar was a full 10 days adrift from the solar calendar.
Now this may not sound like a big deal. 10 days – who cares, right? But the Roman Catholic Church weren’t happy because Easter was getting later and later.
So in 1582 Pope Gregory VIII solved the calendar chaos by omitting three leap days every 400 years. This calendar was also self-named – the Gregorian calendar. However, whilst Europe adopted this new calendar, England did not…
By 1752, England was a full 11 days out of alignment with Europe, and they finally realised they needed to make a change. As such, that year they chose to wipe 11 days from the month of September. This meant that when everyone went to bed on the 2nd September, they awoke the next day and – as if by magic – it was the 14th of September.
This wasn’t just bad news for those who had birthdays between 3rd and 13th of September, it was also bad news for the tax man. He wanted those 11 days! As a result, he added them to the end of the year. So, in 1753, the new tax year started on 5th April.
OK, so we’re still one day out here…
How did we get from 5th to 6th April?
There was still a difference between the Julian and Gregorian calendars. 1800, according to the Julian calendar, was a leap year. But in the Gregorian one, it wasn’t. To solve this, the Treasury decided they’d treat 1800 as a leap year for the purposes of taxation. 6th April has remained the beginning of the tax year ever since.
And there you have it. Not a simple story, and not one that’s likely to come up on a pub quiz. But interesting nonetheless.