Why is a guarantee needed at all?
When goods are moving under transit, the destination customs authority has not yet been paid the duty and VAT that would be due if those goods were imported. If something goes wrong — the truck disappears, the goods are diverted, the seal is broken without permission — customs needs a way to recover the duty that should have been paid.
That is what the transit guarantee does. It is a financial guarantee equivalent to the potential customs debt. If the movement is not properly discharged, customs draws on the guarantee.
Types of guarantee
There are a few different shapes the guarantee can take:
- Individual guarantee — a one-off guarantee for a single movement, sometimes via voucher (the old TC32 system). Cash-heavy and slow; almost never used today for commercial freight.
- Comprehensive guarantee — a single financial guarantee that covers many movements at the same time, up to a ceiling. This is what brokers and large traders use.
- Comprehensive guarantee with reduction or waiver — held by AEO-status traders with proven compliance, allowing them to cover larger ceilings with less cash.
- Cash deposit — for very occasional movements or where the trader has no other facility.
For most UK ↔ EU road movements, comprehensive guarantee is the right answer.
Who provides the guarantee?
The guarantee is provided by the principal — the legal party responsible for the transit movement. In practice, this is almost always a:
- Customs broker
- Freight forwarder authorised as a consignor
- Haulier with their own NCTS authorisation
The principal puts up a bank guarantee or comparable security with HMRC (or the EU equivalent) and is allowed to cover a defined value of open transit at any one time — the reference amount.
Why most traders use a broker's guarantee
Setting up your own comprehensive transit guarantee means:
- Getting authorisation from HMRC (or another customs authority)
- Providing a bank guarantee for a defined ceiling — typically in the £50k+ range
- Maintaining a customs compliance record
- Managing the guarantee balance in real time
For a trader doing five T1s a week, this is overkill. It is far simpler to use a broker's existing comprehensive guarantee — you get the transit benefit without locking up your own cash.
How a broker's guarantee works in practice
- You ask the broker to lodge a T1 for a specific movement.
- The broker checks their guarantee balance — is there room for this movement under the reference amount?
- If yes, the broker uses their Guarantee Reference Number (GRN) on the NCTS declaration.
- NCTS reserves the relevant amount on the broker's guarantee for the duration of the movement.
- When the movement is discharged at the office of destination, the reservation is released.
The trader pays the broker a service fee. The broker's guarantee does the heavy lifting.
What can go wrong with the guarantee?
- Reference amount exhausted — too many open movements, no room for a new one. A good broker monitors this and tops up the ceiling proactively.
- Movement not discharged — the guarantee remains locked until customs accept that the goods arrived or write off the debt.
- Customs debt opened — if the goods are diverted or the seal is broken, customs can draw on the guarantee for the duty owed.
- Guarantee withdrawn — if HMRC or the EU lose confidence in the principal, the guarantee can be suspended, instantly cutting off transit capacity.
These are real risks, which is why traders should make sure their broker has a comprehensive guarantee in good standing and a clear track record on discharges.
Our guarantee
We hold an authorised comprehensive transit guarantee covering all UK ↔ EU movements we lodge. You do not put up cash for individual movements. We monitor every T1 from lodgement to discharge so that nothing sits open and creating risk against the guarantee. Talk to us before your next T1 — we will tell you exactly what is needed and what it will cost.