6 Steps to Become Audit-Ready Using Your CDS Data

By
Adam Wood
February 17, 2026
5 min read

HMRC audits are rarely about a single entry.

When an officer visits, they are looking to build an overall picture of the business’s customs controls. They will ask how declarations are prepared. They will interview key personnel. They will select entries for detailed review. They will test whether the data declared aligns with what was actually imported, paid and recorded internally.

In almost every audit, the common thread is data. Specifically, whether the business understands its CDS data well enough to explain it clearly and confidently.

Becoming audit-ready is about control, visibility and evidence.

Here are six practical steps businesses can take to become audit-ready using their CDS data.

1. Secure And Understand At Least Three Years of CDS Data

HMRC expects businesses to retain customs records for a minimum of four years. In practice, most audits focus on the most recent three.

Accessing your CDS data is the starting point, but audit readiness requires more than downloading files.

You should be able to:

  • See trends in import volumes and values
  • Identify step changes, such as new suppliers, new commodities, or changes in routing
  • Explain why figures have moved year on year

Your CDS data tells a story. Audit risk increases when the business cannot articulate what that story is.

2. Know Your Duty Under Management (DUM)

One of the most common weaknesses identified during audits is a lack of clarity over total duty exposure.

Duty under management is not just what duty was paid. It is the cumulative value of your duty paid and duty saved/mitigated through the use of free trade agreements (FTAs) and special procedures. Importantly, this calculation must be in line with the three year audit window.

Example:

Period                                                                    36 months

Duty Paid                                                              £1,000,000

FTA Claimed                                                        £4,000,000

Special Procedures                                            £5,000,000

Total DUM                                                            £10,000,000

Understanding this matters for two reasons:

  • It highlights financial risk and materiality
  • It demonstrates to HMRC that duty is actively governed, not passively incurred

If a business cannot state its total duty exposure, it is difficult to argue that the risk is being managed.

3. Validate Declaration Accuracy Early And Continuously

Errors are not unusual. Unidentified errors are the problem.

Audit-ready businesses do not wait for HMRC to identify issues. They validate declaration accuracy as part of ongoing controls.

This includes checking:

  • Commodity codes
  • Customs values
  • Preference claims
  • Reliefs and special procedures

Early validation allows errors to be corrected before they become systemic. It also builds credibility.

4. Reconcile CDS Data Against Source Documents And Systems

CDS data should never sit in isolation.

To be audit-ready, businesses must be able to reconcile declarations back to:

  • Commercial invoices
  • Shipping documents
  • ERP or finance systems
  • Broker records

What matters is that the business can demonstrate that:

  • Data has been checked
  • Differences are understood
  • Exceptions are investigated

A clear reconciliation trail is often the difference between a smooth audit and a prolonged enquiry.

5. Conduct Internal Audits And Evidence Them

HMRC does not expect businesses to outsource responsibility for compliance to brokers. The legal responsibility always remains with the importer.

Internal audits are a key expectation.

These do not need to be complex, but they must be:

  • Documented
  • Repeatable
  • Based on full-population data where possible, not small samples

Crucially, the business must be able to evidence that these checks took place. An undocumented control is indistinguishable from no control at all.

6. Establish A Clear HMRC Communication Protocol

When HMRC contacts a business, confusion often follows.

A communication protocol should define:

  • Who owns HMRC correspondence
  • How information is gathered and validated
  • How responses are reviewed before submission

Clear governance reduces response times, avoids inconsistent messaging, and demonstrates organisational control.

Audit Readiness Is About Control, Not Compliance Theatre

HMRC audits are not designed to catch out well-governed businesses. They are designed to identify unmanaged risk.

Businesses that understand their CDS data, actively review it, and can explain it clearly are significantly better positioned when scrutiny arises.

Audit readiness is not a one-off exercise. It is an outcome of visibility, structure, and repeatable controls built around data.

If you can explain your data, you can defend your position.

And that is what HMRC is really looking for.

Adam Wood
Chief Commercial Officer