Advisers filing a self-assessment paper tax return after the 31 October deadline will be hit with a £100 fine - even if there is no tax to pay, or the tax due is paid on time.
HM Revenue and Customs (HMRC) also highlighted a series of further late-filing penalties at three, six and twelve months, which could reach £1,600 if left unpaid.
Its guidelines recommend filing online, which extends the deadline to 31 January. Benefits include automatic tax calculation; immediate online confirmation; and faster processing, so any money owed is repaid more quickly.
However, advisers who intend to submit a paper form, miss the deadline and file online instead will still be fined.
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