Guides / CDS software or a broker · Updated 19 October 2026

Customs declaration service software or a customs broker?

Searching for customs declaration service software usually means one thing: you want to know whether you can file UK declarations yourself. HMRC does not provide a free front end for full import declarations, so self-filing means CDS access plus third-party software. Here is what that involves, and when handing it to an agent is simpler.

This guide is also available in Polish.

The short answer: there is no free HMRC form for full import declarations

HMRC's own guidance is plain about this. Its Customs Declaration Service collection says that if you submit customs declarations yourself, you will need specialist software to interact with HMRC systems, and the guidance on making a full import declaration says you will need to use software that can submit declarations. HMRC does not hand out that software. It publishes a list of third-party developers instead.

So when people search for "customs declaration service software", they are usually facing a choice between two routes:

• File yourself: subscribe to CDS, buy or licence declaration software from a developer, and learn to complete declarations to the CDS data standard.
• Use an intermediary: give a customs agent, freight forwarder or express operator written instructions and let them submit the declaration through their own software.

There is one notable exception on the export side. HMRC runs an online service to make or manage export declarations for goods leaving Great Britain (England, Scotland and Wales) for a country outside the UK. You must be subscribed to CDS to use it. It handles standard export declarations, simplified and supplementary declarations and consolidation under a master reference, but it is an export tool: HMRC's import guidance still points you to software.

What "CDS software" actually means

CDS itself is HMRC's back-end system. You do not log in and type a declaration into it the way you might fill in a tax return. Declarations reach CDS from software that has been built to HMRC's interface, and the response (acceptance, errors, the Movement Reference Number) comes back through the same software. If the general workings of the system are new to you, start with how the Customs Declaration Service works, then come back to the software question.

The HMRC list of software developers is the official starting point, and it comes with three caveats worth reading before you contact anyone:

• HMRC says it cannot recommend or endorse any one product or service over another.
• Developers who have not agreed to publish their details are not on the list, so it is not a complete market map.
• HMRC is not responsible for any losses or expenses you incur using software from the listed providers.

Each entry shows which declaration types the product supports. The categories used on the list are CDS imports, CDS exports, simplified declarations for imports, simplified declarations for exports and customs warehouse. A product that only covers exports will not help an importer, so check that column against the declarations you actually make. We deliberately do not name or rank vendors here.

What you need before you can file yourself

Software is only one piece. To submit your own declarations you need, at minimum:

• An EORI number starting with GB (or XI in Northern Ireland, which has its own eligibility criteria). You can apply for one while subscribing to CDS.
• A Government Gateway user ID for the business (or for yourself as an individual). HMRC says you cannot subscribe with an agent Government Gateway user ID.
• Your Unique Taxpayer Reference, the business address held on HMRC's customs records, the business start date and, for individuals and sole traders, a National Insurance number.
• A completed CDS subscription. HMRC says access is given within 2 hours, or within 5 working days if it needs to make more checks.
• Software that supports the declaration types you need, connected to your subscription.
• A way to pay: for example a cash account or a duty deferment account, set up through HMRC's import duties and VAT accounts service.
• Working knowledge of the UK Trade Tariff volume 3 for CDS, which sets out how each data element is completed.

If several people in your business will use the subscription, HMRC lets you add team members through your business tax account and control what each can access.

Practise before you go live

HMRC offers the Trader Dress Rehearsal service, a free, simulated version of CDS where no payments are taken and licences or quotas are not affected. It is not a shortcut around buying software, though: HMRC lists third-party software from a provider among the things you need to use it, along with an EORI number and any authorisations you hold.

What filing yourself really involves

A full import declaration is not a short form. HMRC's guidance lists, among other things, the customs procedure code, the commodity code, a declaration unique consignment reference, consignor and consignee, the type, quantity and packaging of the goods, transport details and costs, currencies and valuation method, and any certificates and licences.

Timing rules also sit with whoever files. At locations using the Goods Vehicle Movement Service or pre-lodgement, the declaration must be made before the goods board. Elsewhere, where a temporary storage declaration exists, HMRC gives 90 days from the goods being presented to customs. HMRC also says you may be able to declare up to 30 days before arrival, with formal acceptance only once the goods arrive and are presented.

Using a customs agent instead

If you appoint an intermediary, they use their own software and their own CDS access to submit declarations for you. HMRC's guidance on getting someone to deal with customs sets the ground rules:

• The person you hire must be established in the UK for customs purposes.
• They cannot act for you without written instructions, and the instruction must show whether they act for you directly or indirectly.
• Under direct representation the importer remains liable for the customs debt; under indirect representation the agent is jointly liable with you.
• You remain responsible for due diligence on your declarations either way.

You will still want your own EORI number and, if the agent should use your cash or deferment account, HMRC's "set up or view an authority" process lets you grant and remove that access. HMRC also publishes a register of customs agents and express operators to help you find someone. For what happens once an agent takes your file, see how a customs broker files your UK import declaration in CDS.

Software or broker: a quick comparison

As a rule of thumb, self-filing tends to suit businesses with steady, repetitive declaration volumes and someone in-house who can own the process. Occasional importers, removals and mixed or regulated goods usually sit better with an intermediary. Our page on whether you need a broker walks through the decision in more detail.

Related guides

• Advance Tariff Rulings (ATaR): a UK guide

• Customs brokerage explained: what does a customs broker do in the UK?

• Postponed VAT accounting for first-time importers

Sources

• Customs Declaration Service (GOV.UK)
• Get access to the Customs Declaration Service (GOV.UK)
• Software developers providing customs declaration software (GOV.UK)
• Making a full import declaration (GOV.UK)
• Get someone to deal with customs for you (GOV.UK)

General information, not legal, tax or customs advice. Rules change; confirm current requirements on gov.uk or with a registered agent before you ship.