You can still book online if you don't know your vehicle registration or if you will be hiring a car. Simply enter “TBA” (To Be Advised) into the vehicle registration field on the Passenger Details step of the booking process. When you have your vehicle registration details, please add this information to your booking as this will avoid delays at the port. You can do this by logging into your Stena Line user profile using the 'Log in/Sign up’ tab of the home page. After logging in and identifying your booking, simply select the 'Change' tab then select the 'Change vehicle details' option to edit the vehicle's registration details.