There are special rules which limit the ability to change your company’s year end date. A company’s year end date is also known as its ‘accounting reference date’ and is historically set by reference to the date the company was incorporated. Under certain circumstances it is possible to make a change to the year end and for some businesses this can have trading and / or tax benefits.

As a general rule, you can only change the year end for the current or previous financial year. Making a change to a year end date will also change the deadline for filing accounts (except during a new company’s first financial year).

There is no limit to the amount of times you can shorten a year end date but you can only extend the period to a maximum of 18 months once in every five years. The financial year can be extended more often under limited circumstances, for example, when the company has been placed in administration.

A request for a change to an accounting reference date can be made online (preferred and quickest option) using the Companies House online service or by using a postal version of the Change your company accounting reference date (AA01) form. No change can be made to a period for which accounts are overdue.

There is no overriding reason for using one date over another but there are a number of factors to take into account. The most common year end dates are 31 December (to coincide with the end of the calendar year) or 31 March (to coincide with the end of the tax year).