Official customs seals and trader sealing

Find out how to recognise official customs seals and how authorised traders can use their own seals in place of official customs seals.

Find out if your goods need sealing

Use the following guidance to find more information about whether your goods need sealing:

To find out more about the use of seals contact imports and exports: general enquiries.

Check official customs seals

An official customs seal is an indicative seal that a customs officer may apply to identify goods under customs control. It may be applied in addition to a trader’s commercial seal.

If you receive goods in the UK secured by an official customs seal, you must inform your local HMRC control office as soon as they arrive.

Unless you’re an authorised consignee, you must not remove an official seal without prior approval from customs. Unauthorised breakage or removal of an official seal during any part of the journey breaches customs law in both Great Britain (England, Scotland and Wales) and Northern Ireland.

In the UK there is one type of official customs seal currently in use.

Leghorn cableseal wire seal

The body is made of painted aluminium. It bears the words ‘Customs GB’ and a serial number.

The cable is made of steel wire, 1 millimetre in diameter and 180 millimetres long.

How to apply to use your own seals

You need to apply for HMRC authorisation to use your own seals.

We’ll give this authorisation if we agree that you meet the necessary standards.

How to meet the standards

If you’re authorised to use your own seals in place of official customs seals, you must:

  • keep all seals and sealing equipment under lock, with the key being held by a responsible person of your company
  • keep a permanent stock record which must be produced to a customs officer on request which shows the:
    • receipt
    • serial numbers
    • use of the seal
    • disposal of the seal
  • regularly inspect and balance your seal stocks to prevent interference or substitution
  • keep all defective and used seals available for inspection by customs
  • agree how you will dispose of the seals with customs
  • clearly show the marks and numbers of the seals on documents accompanying the goods
  • apply or remove the seals yourself or allow only responsible employees you have authorised to act for you apply the seals

You must only use seals that agree with established standards.

International standards

Your seal will meet the requirements if it conforms to the International Standard No. 17712 2013 ‘Freight containers – Mechanical Seals’

This international standard for seals is recognised by all Common Transit Convention (CTC) countries — this includes the UK and the EU,

It is also recognised by customs authorities in other countries around the world.

Some countries insist that it should be used for all consignments arriving at their ports.

The customs authorities of a Common Transit Convention member country will accept the seals that have been approved by the customs authorities of any other CTC country — unless they have information that the particular seal is not suitable for customs purposes.

We recommends that seals with high-security features should be used for all international transports whenever possible.

UK standards

The seals must:

  • remain intact and securely fastened in normal use
  • be easy to check and recognise
  • be made of a material that:
    • is resistant to accidental breakage
    • prevents undetectable falsification
    • leave traces of any breakage or removal that are visible to the naked eye
  • be designed for single use or, if intended for multiple use, be designed so they can show a clear, individual identification mark each time they are used
  • each show a permanent unique identifying mark and be serially numbered and used in sequence

Identification marks of seals must be impossible to falsify and difficult to reproduce.

The form and dimensions of the seals can vary depending on the method of sealing used. You must make sure that identification marks are easy to read no matter what the dimensions of the seal are.

If an incident happens when using an official customs seal or your own seal

If you discover a seal has been tampered with or broken on:

  • your own premises, you should report the facts to your local control office
  • a vehicle or container and there’s also extensive damage to the vehicle, container or goods, you should report to your nearest customs office immediately
  • a vehicle or container in which you’re carrying goods under customs control, you should report to customs at your destination as soon as you arrive there

The customs officer may ask you to explain how any seal breakage and damage occurred.

In all cases of unauthorised seal breakage, you must get a customs officer’s permission before you remove or unload the goods originally secured by that seal.

If an accident or other incident occurs during the transport of the goods

You must notify customs of the accident or incident as soon as possible.

Whenever possible, you should get prior authorisation from customs to break seals or transfer goods from one vehicle to another.

An account of the incident must be noted on the transit declaration. The goods and the declaration must be presented to the nearest customs authority. When customs are content that the operation may continue, they will reseal the goods and endorse the declaration accordingly.

Your rights and obligations

Read the HMRC Charter to find out what you can expect from us and what we expect from you.

Published 14 December 2021
Last updated 30 January 2024 + show all updates
  1. We have updated guidance on how to apply for approval to use your own seals.

  2. The 'Check official customs seals' section has been updated with information about breakage or removal of official seals. 'Trader seals which are accepted by HMRC from 20 June 2022' has been updated to show seals accepted by HMRC from 20 October 2023.

  3. The Acme ‘T’ lock seal is no longer an official customs seal and has been removed from the 'How to recognise the types of seal' section. There is now only one type of official customs seal in use.

  4. Guidance for seals manufacturers explaining how they can apply for acceptance of their products in the 'UK standards' sub-section of the 'Apply to use your own seals' section has been removed. Signum Services Ltd no longer operate the HMRC ‘Security Seals Testing Authority’. The address to write to if you have suggestions to improve this notice has also been updated.

  5. Contact information for the Security Seal Testing Authority has been updated in the 'UK standards' section.

  6. A new seal has been added to 'Group 1 — seals that can withstand a force of 1,000 kilograms'.

  7. First published.