T1 refers to the EU external transit procedure, mainly used to move non-Union goods under customs control. It allows import formalities to take place at destination, with duties and taxes suspended during transit. See the European Commission’s transit overview.
An operation-specific deadline
The procedure holder must present goods at destination within the prescribed time, with the required references and identification measures. There is no universal duration for every road, rail or inland-waterway journey. Check your operation’s deadline and the obligations described by French Customs.
Ending and discharging transit
Physical arrival alone does not prove discharge. Customs processing must establish that the procedure ended correctly. Copying a T1 reference into another document does not itself provide that evidence.
Ask your representative who handles presentation at destination and how completion will be followed up. Goods under T1 are not freely available for consumption.
Keep the references together
Retain the transit reference, relevant customs offices, deadline, transport documents and confirmation of destination processing. In the shipment file, those references help the carrier, declarant and receiving team coordinate.