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Millions Face Tax Code Errors: Check Yours Now!

1/17/2026

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Summary

Story summary

Martin Lewis, founder of Money Saving Expert, cautions that millions of UK tax codes contain errors and employees must verify their codes themselves.
Lewis notes that incorrect tax codes can lead to overpayments or underpayments of taxes and financial consequences.
The typical tax code is 1257L, allowing £12,570 of annual tax-free income.
He urges employees earning over £12,570 to check their tax codes annually to avoid unexpected tax bills.

History

Historical Context

In 1996, the UK government introduced significant tax reforms, including the 1257L code, allowing £12,570 of tax-free income to simplify tax calculations for employees. This reform was part of the broader Tax Law Rewrite Project, which aimed to modernize tax legislation from 1996 to 2010. Despite these efforts, many workers still face challenges verifying their tax codes, highlighting ongoing issues in tax administration.

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Story summary

Martin Lewis, founder of Money Saving Expert, cautions that millions of UK tax codes contain errors and employees must verify their codes themselves.
Lewis notes that incorrect tax codes can lead to overpayments or underpayments of taxes and financial consequences.
The typical tax code is 1257L, allowing £12,570 of annual tax-free income.
He urges employees earning over £12,570 to check their tax codes annually to avoid unexpected tax bills.

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