The Islands in the South of Thailand are even more accessible from the mainland with daily ferry services connecting them. If you are staying in Krabi Town and would like to transfer to Railay Beach or from Railay Beach to Krabi Town there is no direct ferry service offering this.
If you stay in krabi town you would need to travel to Ao Nang which is around 30 minute drive away. From Ao Nang you can then enjoy the daily ferry service listed below which stops at Railay on the way to Koh Lanta. Or an alternative is when you arrive in Ao Nang you may hire a private long tail boat to Railay Beach which departs when you arrive.
Below is the Ferry timetable and the name of the company operating the transfer. Tickets can be bought on the mainland or the Islands from any resort or local travel agent. The travel agent can also arrange your taxi to and from Ao Nang.
Please note the above service may only operate in the high season due to less tourists and the winds changing directions creating large waves.