Is there a time limit on HMRC collecting a debt

In England and Wales there is effectively no time limit on HMRC taking court action to recover tax that has been established, because section 37(2)(a) of the Limitation Act 1980 says the Act does not apply to Crown proceedings to recover tax, duty or interest on them. An unpaid tax debt therefore does not expire with age. The six year limitation period does, however, apply to some sums HMRC collects that are not tax, including National Insurance contributions and contract settlements.

Is this the same as the time limit for HMRC to assess tax?

No. There are two separate questions. The first is whether HMRC can still establish the liability, by assessment or amendment of a return. For income tax and capital gains tax that is normally 4 years from the end of the tax year, 6 years for careless behaviour and 20 years for deliberate behaviour, as HMRC’s table at CH56100 shows. Our page on how far back HMRC can go covers those rules.

The second question, covered here, is how long HMRC has to collect a liability once it has been established, for example tax shown on your own return, a closure notice amendment that was not appealed, or an assessment that became final. Once that point is reached, the age of the debt gives no general defence.

What does the Limitation Act 1980 say?

Section 9(1) of the Limitation Act 1980 sets a six year limit for actions to recover any sum recoverable by virtue of an enactment, running from the date the cause of action accrued. Section 37(1) applies the Act to proceedings by the Crown in the same way as to proceedings between private parties. But section 37(2)(a) carves out “any proceedings by the Crown for the recovery of any tax or duty or interest on any tax or duty”.

HMRC’s Debt Management and Banking Manual at DMBM595080 draws the conclusion directly: because section 37(2) excludes proceedings to recover tax, duty and interest on them, “there is no time limit for those debts”. The Limitation Act extends to England and Wales; the rules in Northern Ireland and Scotland are covered below.

Which HMRC debts do have a six year limit?

DMBM595080 lists debts HMRC collects that are not tax and are therefore subject to the Limitation Act, including:

• National Insurance contributions;
• contract settlements;
• tax credit and Child Benefit overpayments;
• recoveries of statutory payments such as Statutory Sick Pay and Statutory Maternity Pay;
• overpaid Child Trust Fund contributions;
• student loan repayments; and
• National Minimum Wage Act penalties.

For these, HMRC must start action within six years of the original due date. DMBM595080 explains that “action” means lodging a complaint in the magistrates’ court, issuing a county court claim form or levying distraint. DMBM527120 adds that once action has been started in time, a limitation defence fails and cannot be raised later, for example after judgment.

Can the six year clock be restarted or delayed?

Yes. DMBM595080 says the limitation date can be advanced by:

• a payment made against the debt (where tax and National Insurance are collected together, HMRC assumes a payment on account is made against both unless the debtor says otherwise);
• an acknowledgment of the debt, which must be explicit and unequivocal; or
• concealment by the debtor of material facts that prevented HMRC pursuing the debt.

On concealment, DMBM527140 explains that section 32(1)(b) of the Limitation Act 1980 postpones the start of the period where a relevant fact has been deliberately concealed, until the creditor discovered or could with reasonable diligence have discovered it. HMRC looks at whether returns were filed and how late.

How does this affect Class 4 National Insurance?

Class 4 contributions are collected through Self Assessment alongside income tax but remain National Insurance, so limitation can be relevant. DMBM525940 explains that the due date for both tax and Class 4 under Self Assessment is 31 January after the end of the tax year, and for a discovery assessment it is 30 days after the notice where payment is not postponed. Those due dates fix when the six year period starts for the Class 4 element. The income tax on the same return is not affected.

What about Northern Ireland and Scotland?

In Northern Ireland the Limitation (Northern Ireland) Order 1989 applies. DMBM527120 says article 74(2) excludes “tax or duty or interest thereon” but not National Insurance, so the position mirrors England and Wales.

In Scotland the Prescription and Limitation (Scotland) Act 1973 applies. DMBM595080 says it provides a 20 year limit for collecting debts, including National Insurance, while certain debts such as settlements fall under a five year prescription after the last effective action. The period is interrupted by a relevant claim or a relevant acknowledgment, such as a payment on account.

What happens once HMRC has a judgment?

HMRC’s view, at DMBM665210, is that in England and Wales the Limitation Act does not stop enforcement of a judgment after six years. Relying on Ridgeway Motors (Isleworth) Ltd v Altis Ltd, HMRC says it can still use charging orders, third party debt orders, attachment of earnings orders, warrants of execution (with the court’s permission) and insolvency proceedings based on the judgment. HMRC also has its own powers, including direct recovery of debts from bank accounts and taking control of goods.

How might this work in practice?

Illustration only. Mark, a self employed decorator in England, filed his 2017/18 return on time showing £4,000 of income tax and £900 of Class 4 contributions, but paid nothing. HMRC contacts him in 2026. The six year period for the Class 4 element ran from its 31 January 2019 due date, so unless Mark paid something, acknowledged the debt in clear terms or HMRC can show concealment, a limitation defence may succeed for the £900 if HMRC has not started court action. The £4,000 of income tax and the interest on it are not subject to any limitation period, so Mark still owes them.

What mistakes do people make?

• Believing a tax debt becomes unenforceable after six years, as many consumer debts do.
• Confusing assessment time limits with collection.
• Making a payment or writing to admit an old National Insurance debt without realising it can restart the clock.
• Assuming that a judgment over six years old cannot be enforced.
• Applying English rules to a Scottish debtor.

If an old debt is genuinely unaffordable, a Time to Pay arrangement is usually the practical route. Where HMRC sat on information for years before asking for the tax, see remission of tax for HMRC delay.

If HMRC opens a check into your return, tax investigation insurance pays your accountant’s fees. Solar Protect cover pays up to £100,000 with no excess; it never pays tax, interest or penalties. Read how our cover works or get a quote.

Related Accountapedia entries

• Is there a time limit for prosecuting tax fraud
• HMRC county court claims for tax debts
• Is there VAT on cryptoassets
• The 12 year time limit for offshore tax
• Writing off a debt in the books

Sources

• legislation.gov.uk: Act 1980 c. 58, section 37
• legislation.gov.uk: Act 1980 c. 58, section 9
• GOV.UK: Manual page CH56100
• GOV.UK: Manual page DMBM595080
• GOV.UK: Manual page DMBM527120
• GOV.UK: Manual page DMBM527140
• GOV.UK: Manual page DMBM525940
• GOV.UK: Manual page DMBM665210

Reviewed by Christine Anderson, Broker, Solar Protect. Last reviewed 24 October 2026. Part of Accountapedia, the Solar Protect guide to UK tax and accounting. This page is general information, not personalised advice.