Right. An explanation of why the UK tax year starts on such a weird date.

in the early 1700s, the tax year started on New Year's Day. But for obscure historical reasons, New Year's Day was 25th March (Lady Day).

So, for example, 24th March 1749 was followed by 25th March 1750. Seems weird to use today. But that's just the way it was. Because religion is weird.

But in 1751, Parliament decided to do away with that weirdness by moving New Year's Day to 1st January. So 31st December 1751 was followed by 1st January 1752.

The accountants weren't sure that their systems could cope with a short year, so they insisted on keeping the end of the tax year on the same date. So it would have remained at 25th March... EXCEPT...

Why make just one big calendar change when you can make two? At the same time as moving the New Year, parliament also switched the UK from the Julian Calendar to the Gregorian Calendar.

By 1751, these two calendars were eleven days out of step. Parliament solved this by just dropping eleven days from September 1752. So Wednesday 2nd September 1752 was followed immediately by Thursday 14th September 1752.

Again, this confused the accountants, who couldn't cope with a tax year that was missing eleven days. So they moved the end of the tax year by eleven years (to 6th April) to compensate.

And it has stayed like that for almost 300 years. The joys of the British tax system.