Passenger ferries to Koh Lanta only run between the months of November to April so if you are wanting to get to Koh Lanta during the low season months of May until the end of October you will need to either take a mini van service or a taxi to the island. Below is a schedule of places you can catch ferries from and at what times.
From Koh Phi Phi
There is both a speedboat service and a ferry service that will take you from Koh Phi Phi to Koh Lanta. Journey time is approximately an hour and 15 minutes both leave from Ton Sai Pier.
From Koh Phi Phi to Koh Lanta 11.30am and 3.00pm
From Koh Phi Phi to Koh Lanta 10.30am
There is talk of this service running once a day during the low season but so far it has yet to materialise but may be worth asking about.
From Koh Lipe
There is one speedboat service per day during the high season connecting Koh Lipe and Koh Lanta and stops of at Ko Ngai Ko Mook Kradan and Bulone along the route. The Journey time is 3 hours approximately.
Koh Lipe to Koh Lanta - 09:00am
You have the choice of a couple of ferry services that run from the island of Phuket to Koh Lanta. Firstly a service that runs once a day via Koh Lipe or twice a day via Ao Nang/Railay. Both services take 4 hours Approximately.
From Phuket to Koh Lanta
Via Koh Phi Phi - 08.30am
Via Ao Nang / Railay - 08.30am and 1.30pm
Trang To Koh Lanta - 08:00am (Takes Approximately 1 Hour)
Krabi to Koh Lanta - 11.00am (Takes Approximately 2 hours)
From Ao Nang/Railay
From Ao Nang/Railay to Koh Lanta - 10.30am 3.30pm (Takes Approximately 2 hours 15 mins)
Boats leave from Nopparat Thara pier, going via Railay Wes / Tonsai beach.
With passenger Ferries only running during high season the only way to access the island during May and October is by driving and taking one of the car ferries to the island. The Ferries leave regularly from Hua Hin Pier between Krabi and Trang until 10pm each night. All Mini Van services will bring you here direct during the low season and the price of the ferry will be included in your ticket. You will have to que for the next available ferry once at the pier but the last few years has seen a rapid decrease in waiting times.