What time do I have to arrive at the terminal?

Vehicles: Please check-in at the port at least 30 minutes, but not more than 1 hour, before departure time. 

Foot passengers: Please arrive at the terminal at least 15 minutes prior to departure to allow time to purchase your tickets and board the ferry. If arriving by train at Portsmouth Harbour you should allow at least 10 minutes for connecting between trains and the catamaran.  

For operational reasons ships may have to sail a little before or after advertised sailing times.