Why does the tax year end on April 5th?

If you look around at how other nations collect tax from their residents, you will notice that the vast majority run personal taxation from the 1st January. This seems a sensible place to start any tax system but funnily enough the 1st January only became the start of the year in relatively recent times. Many early cultures actually started counting the year from the spring equinox – or more specifically spring festivals that celebrated new life. This was the case with Early Romans who had March as the first month of the year – and even now is still reflected in month names (septem is latin for seven, as in seventh month of the year, with octo, novem and decem being latin for eight, nine and ten).

Other than starting in March, the early Roman calendar also had a standard year that was 355 days long. This is of course less time than it takes to orbit the sun, so their calendar occasionally had to squeeze in a thirteenth month to adjust the date back in line with the solar calendar. The Romans hadn’t done a particularly good job of this and by the time of Julius Caesar they had missed out enough months to be celebrating the longest day of the year in March!

Julius Caesar, with help from the astronomer Sosigenes, came up with a solution – known as the Julian calendar. It had been worked out that it took 365 and ¼ days to orbit the sun so the new calendar adopted the basic 365-day year we now know and removed the haphazard thirteenth month. The new calendar had to align with the seasons so they needed an extra-long initial year of 445 days – which no doubt caused some serious consternation at the time. This just left the quarter day to account for and it was agreed to add a leap day to February every fourth year. The Romans rather curiously repeated the 23rd February, but this eventually became the 29th February. Job done!

However, what the Romans hadn’t realised was the Julian calendar didn’t need to add an extra day every four years – the new system needed ever-so-slightly less adjustment than this. It wasn’t a problem for quite some time, but by the 16th Century, the Julian calendar had over corrected by adding ten too many days to the calendar. The spring equinox was now on the 11th March and creeping ever earlier. This greatly concerned the Catholic church, so under the direction of Pope Gregory XIII, another solution was agreed – known as the Gregorian calendar.  The Catholic world would add ten days to the date so the day after the 4th October 1582 would became the 15th October 1582. To ensure that the problem of adding too many leap days wouldn’t be repeated, a formula was agreed to skip leap days at designated intervals (if you want to add it to your diary, the next time where we skip what you might think would be a leap day is 2100).

France, Italy and Spain immediately adopted this new calendar, but the rest of Europe adopted the new calendar over an extended time. Most nations added the ten days in one go, but Sweden, for example, omitted leap years until they were in line – so for forty years the date in Sweden wasn’t the same as anywhere else. Britain, not one to follow what it considered Catholic interference at the time, was still using the Julian calendar well into the 18th century. By this point, because of an extra leap day that wasn’t, Britain was eleven days out from most of Europe.

Further dating difficulties occurred because mid-18th century England considered that the legal year started on the 25th March – a date that doubled as a religious festival in spring and didn’t move (unlike Easter). Confusion reigned regarding dates! The date of Elizabeth the First’s death was officially the 24th March 1602 in England – as it wasn’t 1603 until the following day. Scotland had adopted the 1st January as their start to the year from 1600, so Scotland considered the same date to be the 24th March 1603. Across the channel, however, Catholic calendars thought it was the 3rd April 1603. Goodness know Most other nations collect personal taxation from the 1st January. But our calendar hasn’t always been the same. If you’ve ever wondered why the most significant date in the tax year is 5th April, our article explores this bit of financial planning trivia. s what the date was in Sweden!

Throughout much of the 17th and 18th centuries, documents needed to account for where as well as when they were dated. Informal dual dating that translated a date into other possible dates helped, but was not in wide use. It was therefore entirely possible to respond to a letter before it was sent and there are reports of armies showing up for battle on the wrong day (or perhaps exactly when they wanted to?)

So the Calendar Act 1750 was brought to the Houses of Parliament to correct all this. To begin with, from 1752, the Act set the start of the year as the 1st January. This meant England’s 1751 was only 282 days long. The Act also moved Britain to the Gregorian method of adjusting for leap years and set the rules for calculating Easter. It further decreed that the day after Wednesday 2nd September 1752 was to be Thursday 14th September, meaning that for the second successive year, the year had fewer days than had been expected. No doubt calendar makers were pulling their hair out!

The government of the day talked up the changes but there was still widespread reluctance from some of the population in accepting Catholic ways. Others apparently believed this Act might shorten their life by eleven days. It’s often reported that there were riots, with people demanding their eleven days back. This is believed to be an exaggeration however there were genuine concerns that rents, payments and debts would need to be settled eleven days earlier than otherwise would have been necessary under the previous calendar system. So the Act also specified that deadlines for debts and contracts be set back by eleven days so no one should gain or lose by the change in calendar.

Accounting practice in 18th Century Britain took the view that the first day of a legal year marked the end of the accounting period – not the beginning. So the day by which tax had to be paid and accounts settled was the end of the 25th March. With the eleven-day shift, this moved to the end of the 5th April, allowing the new financial year to start the day afterwards. It wasn’t actually moved until 1758 and only for a tax on how many windows an individual had, but the new accounting period became the 6th April and there it remains until this day.