HM Revenue and Customs says that its latest data – one week ahead of the January 31 Self Assessment deadline – shows 3.8m people yet to file their tax return.

Many thousands are believed to be landlords. 

HMRC says it’s expecting more than 12.1m tax returns to be filed for the 2022 to 2023 tax year along with any payment that is owed. By the end of Wednesday January 24 – the day before yesterday – more than 8.3m online returns had been received. 

The penalties for late tax returns are an initial £100 fixed penalty, which applies even if there is no tax to pay, or if the tax due is paid on time.

After three months, additional daily penalties of £10 per day, up to a maximum of £900 are levied; after six months, there’s a further penalty of five per cent of the tax due or £300, whichever is greater.

After 12 months, another five per cent or £300 is charged, whichever is greater.

HMRC will consider a customer’s reasons for not being able to meet the deadline. Those who provide a reasonable excuse may avoid a penalty.

But there are also additional penalties for paying outstanding tax late. These are five per cent of that unpaid at 30 days, six months and 12 months. Interest will also be charged on any tax paid late.

An HMRC spokesperson says: “If you are a Self Assessment taxpayer, now is the time to take action and get your return done. People can familiarise themselves with the process by checking out HMRC … on GOV.UK. Once a tax return is submitted, it’s easy to find out what’s owed and to pay online or using the HMRC app. Just search ‘pay my Self Assessment’ on GOV.UK to find out more.”

For anyone unable to pay in full, HMRC says it wants to help find an affordable way to pay the tax they owe. They may be able to set up a Time To Pay arrangement and can find out how to do this online, without speaking to HMRC, if they owe less than £30,000.