In a press release, HMRC disclosed receiving 11,027,962 self-assessment tax returns for the 2022/23 tax year. With 12,187,811 taxpayers expected to file, this indicates that over 1.1 million individuals missed the 31 January deadline - a 10% increase from the previous year.

Despite projecting many late filers, HMRC received 500,000 more returns than anticipated, potentially suggesting that fiscal changes prompted hundreds of thousands to enter self-assessment for the first time.

The deadline day saw a rush, with 778,068 taxpayers filing and 32,958 waiting until the final hour. There were 61,549 returns filed between 4:00 pm and 4:59 pm.

Myrtle Lloyd, HMRC's director general for customer services, expressed gratitude to millions meeting the deadline but added:

"Anyone who has yet to file and is concerned that they cannot pay in full may be able to spread the cost of what they owe with a payment plan."

Late penalties extend beyond the initial £100 fine. A 5% penalty applies to unpaid tax at 30 days, 6 months, and 12 months, coupled with interest on late tax payments.

Late payment interest is currently at 7.75%, the highest in 16 years since January 2008. Those filing at the last minute should swiftly submit to avoid additional charges beyond the £100 penalty.

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