One of the first limited company filing requirements is the annual statutory accounts. These should be filed with Companies House every year, even if your company has not been trading (in which case you would simply file a set of dormant company accounts).
The deadline for limited company accounts is nine months after your company’s year end (which is always the last day of any given month). For example, if your year end is the 31st of March 2019, your limited company accounts need to be filed nine months after this date, so the deadline would be 31 December 2019.
It’s really important to file your accounts on time – failure to do so can result in very high penalties, which can easily be avoided by good organisation!