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HMRC internal manual

Debt Management and Banking Manual

Debt and return pursuit: NIC: class 1 NICs: NICO cases - DTO actions

On receipt of the papers from NICO, the DTO will acknowledge the case within 28 days by completing the tear-off slip from the transfer form.


You should not try to enter these cases on IDMS.

If you have an existing debt you will need to review the overall position in the light of the new debt, and follow the process for PAYE underpayments.

Issue a manual warning letter for all outstanding debt, using the text of the IDMS 10.

If there are no other debts, issue an IDMS 10 type letter for the National Insurance debt.


DTOs may take any of the normal methods of enforcement to secure payment of these debts, and are responsible for accounting for all enforcement costs incurred in relation to them.

Certificates of debt

If you need a certificate of debt, send a completed P104 certificate to NICO, quoting the NICO reference and the name of the caseworker.

Recovery proceedings checks

You must carry out an RP check as normal before taking any new or further enforcement action (DMBM615040). You should:

  • contact the Caseworker in NICO who referred the case to confirm that the debt is still outstanding
  • contact DMB Newcastle Banking Unit (NBU) on (This content has been withheld because of exemptions in the Freedom of Information Act 2000) (DMBM615170).


Payments should be sent with a PS1(NICO) payslip to DMB Banking Shipley following the guidance in Helpcard BA014: Preparing and sending direct taxes cheques for processing.

The payslip should include:

  • the originating office’s reference number
  • the area/destination code quoted by NICO on the transfer form so that the payment can be allocated correctly.


Interest on Class 1 National Insurance is chargeable from 19th April after the end of the tax year, under Paragraph 17 of Schedule 4 to the Social Security (Contributions) Regulations 2001 to the date of payment.

NICO will calculate the interest due to the date the papers are referred, and provide a daily rate of accrual. Interest continues to accrue until payment is made in full.

When you collect an amount of interest that is greater than originally notified, you should show the full amount of interest collected on the payslip. NICO will increase the interest charge to accommodate the payment.

Interest in enforcement cases

When enforcement proceedings are taken the DTO should tell the originating office by memo of the amount of interest awarded by the court in judgment (CCP) or order (SP), so that the originating office can amend the interest accounting record.