There are two options for travel between Trinidad and Tobago - by ferry and by air.
Travelling by air will cost TT$300 US$50 round trip or TT$150 one way per person. There are twelve flights per day. Flight time is approximately 25 minutes each way. Caribbean Airlines (http://www.caribbean-airl...) runs the service.
There are two types of ferry service - fast and conventional.
Travelling by fast ferry costs TT$50 one way and TT$100 return. Vessels are the T&T Express and The T&T Spirit, which are both owned by the Port Authority of Trinidad and Tobago. The journey is approximately 2.75 hours. The Express is the faster of the two ships, but the Spirit is newer and has better facilities.
Travelling by conventional ferry costs TT$37.50 one way and TT$75 return, but the journey is approximately 5.5 hours. Vessels are the MF Panorama and Warrior Spirit.
Vehicles can be taken aboard the ferry, but this incurs a different charge which varies by size and weight. A return trip for a private car costs TT$350. This includes the cost of the driver. You are unlikely to be able to take a rental car on the ferry since you need to show vehicle registration documents.
From 1 November 2009, only tickets for same day travel can be purchased at the ferry terminals in Port of Spain and Scarborough. For advance tickets, you must purchase tickets from some select travel agencies - at peak times tickets sell out quickly, particularly for vehicles. For ferry schedules and travel agencies, see the Port Authority website (http://www.patnt.com/ferr...).