If you are travelling between the UK and the Channel Islands, then you do not need your passport for travel. However, we recommend that you have a suitable proof of identity with you when you travel (e.g. driving licence or other photo ID)
But don't forget you'll need a valid passport OR National Identity Card for travel to and from France.
Passengers travelling to and from St. Malo must ensure that their passport(s) OR National Identity Card(s) is available for inspection and the correct and valid documentation is being carried. Visas are required by some non EEC nationals. If you are travelling to or from France, we ask that you complete your advance passenger information (API) at least 24 Hrs before your travel. You can complete this here. If you have not supplied this information before you travel, we’re sorry but you won’t be able to travel.