T1 transit UK is a customs document allowing goods to be transported in transit through the United Kingdom (e.g. PL→UK→IE, PL→UK→Norway) without paying duty and VAT in the UK. It derives from the Common Transit Convention (CTC) — an international agreement between the EU, UK, EFTA (Norway, Iceland, Liechtenstein, Switzerland), Turkey and several Balkan countries. The document is managed by the electronic NCTS system (New Computerised Transit System), currently NCTS Phase 5.
Issuing a T1 requires four elements:
- Customs guarantee — comprehensive guarantee (CGU) proportional to the goods value, typically 0.1–0.3% of value
- MRN number from NCTS — generated after declaration submission
- Authorised consignor (on the UK side) or physical attendance at the office of departure
- Closure of transit at the office of destination within a maximum of 7 days of issuance
Standard cost: £75–£125 per single T1 + guarantee proportional to goods value. EC issues T1 in an average time of 4 hours from contact (express 2h SLA available).
T1 is required in three main scenarios:
- Multi-leg route PL→UK→another country (IE, NO, CH, IS) — the most common case for Polish carriers serving the UK→Ireland route
- Goods entering a UK customs warehouse (customs warehouse) and then re-exported outside the UK
- Goods value >£100k where VAT exposure (20% × £100k = £20k) requires a security
T1 is not needed for direct export PL→UK with delivery to a UK customer — in that case we use a standard export declaration + UK import declaration.