Glossary

What is a Supplementary Declaration?

A Supplementary Declaration is the full customs declaration submitted after goods have already been released, completing an entry that began as a Simplified Frontier Declaration or an EIDR record. It carries the complete data and settles the duty.

What does a Supplementary Declaration do?

It converts a reduced frontier entry into a complete customs record full commodity codes, valuation, origin, procedure codes and any licences. Duty and import VAT are calculated at this point and drawn from the trader’s duty deferment account, weeks after the goods themselves have moved on.

Who must submit one?

  • Any trader releasing goods under CFSP, whether the frontier entry was an SFD or an EIDR record.
  • The declaration is filed against the original entry’s reference, so records must tie back to the frontier release.
  • A Final Supplementary Declaration (FSD) then reconciles the period’s totals for HMRC.

Why the deadline matters

Late or missing Supplementary Declarations are among the most common reasons HMRC suspends a CFSP authorisation. The goods are already in free circulation, so an unfiled declaration means duty is owed but unaccounted for — a liability sitting on the importer with no cargo left to hold.

iCustoms links every Supplementary Declaration back to its frontier entry, so nothing falls through the month.

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