Why Transit Needs a Guarantee
A transit declaration suspends duty and import VAT while goods move under customs control. If the goods leak into the customs territory without being properly cleared — say, an unloaded container vanishes between offices — those taxes become due.
The guarantee is the security HMRC takes to cover that risk. Every movement must be backed by one. The only question is what kind of guarantee suits your operation.
Comprehensive vs Individual Guarantees
- An Individual Guarantee covers a single movement. It is simple, but expensive per movement and slow to arrange in volume.
- A Comprehensive Guarantee (CGU) is a standing facility that covers many movements up to an agreed ceiling. Ideal for regular traders.
If you move goods under transit more than a handful of times per quarter, a CGU is usually the right answer.
How a CGU Works in Practice
HMRC sets a reference amount — typically the maximum customs debt that could arise from your movements over a one-week reference period. You provide financial security (cash deposit, bank guarantee or guarantor's undertaking) covering that amount.
Each transit movement consumes part of the reference amount until it is discharged. When it discharges, the capacity is released back into the pool.
You receive a Guarantee Reference Number (GRN) which is quoted on every transit declaration. Manage that GRN carefully — a movement that exceeds available capacity will be rejected.
The Application Process
- Customs compliance check. HMRC will look at your declaration history, your audit trail and your record-keeping. Bad data is the most common reason CGU applications are delayed.
- Financial assessment. HMRC assesses whether you can be granted a guarantee waiver (reduced security) or whether full security is required.
- Approval. Once granted, you receive the GRN and ceiling. The CGU is renewed annually.
Expect 8–12 weeks end-to-end. If you need to move under transit before approval lands, individual guarantees can be arranged as a bridge.
What Often Goes Wrong
- Underestimating the reference amount. A single high-value movement can exceed your ceiling and block traffic.
- Letting the GRN expire. Renewals are not automatic — they need to be filed.
- Not monitoring utilisation. Without daily visibility on what your guarantee is carrying, you find out only when a declaration is rejected.
A specialist transit broker manages all three — and applies for the CGU on your behalf if you don't already hold one.