The 440 Kilometers from Myeik to Kawthaung have been almost everywhere described as boring and not worth it.Will it depends how you look at it. Once we saw some wild elephants between the palm oil plantation and then there are the villages along the way and all the simple things. Yes it is long min 8 hours in a private car and 11 hours in the VIP Bus, but at the end it is the journey, which matters. You can break up the ride with overnight in Tanintharyi (simple guesthouse) and Bokpyin (very simple guesthouse).
Flights
There are two or three direct flights connection between Myeik and Kawthaung (depending on the season) with Myanmar Airways. The airline will fly Wednesdays, Fridays and Sundays for a starting price of 89 USD. Flight departs on different times from Myeik and just after lunch from Kawthaung. For exact times it is better to visit their website (www.flymna.com).
Bus & Minivan
The daily option by land is possible now without any problems and permits. The ride takes something between 10-12 hours depending on the driver. The road is sometimes windy, occasionally bump, but overall in good conditions. The southern stretch from Bokypin to Kawthaung is boring as there is mostly Palm Oil plantation. The northern part from Myeik to Tanintharyi is actually nice to look at if you have the change to travel buy day. You can also charter a boat from Tanintharyi to go down to Myeik (The local ferry was also suspended as roads have improved significantly.)
For those who have time you can stop in Tanintharyi (AC Guesthouse, 30000 Kyats single and 40000 Kyats double with breakfast ) as well as Bokpyin (Simple Guesthouse, shared bathroom, prices change from face to face, but should be under 10000 Kyats).
Here is a little bus table, but times might vary throughout the season. So please let me know if you have experienced different times and prices:
From Myeik to Kawthaung - VIP Bus (11:30 AM) - 30500 Kyats
From Myeik to Kawthaung - AC Bus (11:30 AM-12:30 PM) 23500 Kyats
From Myeik to Kawthaung - Minivan (6:00 AM. 12:00 PM, 5:00 PM) - 25000 Kyats
From Myeik to Kawthaung - Cargo Bus (7:00 PM) - 20000 Kyats
From Kawthaung to Myeik - VIP Bus (12:30 PM) - 30500 Kyats
From Kawthaung to Myeik - Minivan (6 AM, 12:00 PM, 5:00 PM) - 25.000 Kyats
Boat
Some of you will say I read something about a romantic ferry seven hour ride through the Archipelago. Yes this ferry rides did exits until December 2015. Then the road link of 440 kilometers was completed and the locals stayed on the bus. Finally the ferry was not sustainable anymore. Also there is no more ferry boat from Dawei to Myeik.
Border crossing
Travel between Kawthaung (Myanmar) - Myo Ma Jetty and Ranong (Thailand) - Saphan Pla is possible daily even on public holiday from 7 AM to 5 PM. Arriving in Thailand gives you usually a free visa, but better check with your Thai Embassy. Arriving in Myanmar (Burma) you will need a valid Burmese Visa to cross into Myanmar as a Western Foreigner. Exceptions: Japanese, South Korean and Singaporeans get a free entry visa on arrival at this border.
From the 01.09.2016 you will be able to enter this border with an E-Visa, which you can obtain online. (http://evisa.moip.gov.mm/NewApplication.aspx)
Simple take a long tail boat around 50-100 Baht per person from Myoma Jetty to cross the river to get to either site. Charter boat from 300-500 Baht or up. Be aware that you can get stuck in Kawthaung if there are no boats going due to weather conditions.
There are visa exceptions that you can stay in Kawthaung up to 14 days if you pay 10 USD, but then you are not allowed to leave the 24 Mile (40 KM) city boundaries and enter the islands.
The Mawdaung / Singkorn border near Myeik is only open for Thai and Burmese Tourists these days. Currently the road is getting upgrade and I hope we can see this crossing opening in the next 1-2 years. You are allowed to travel to Mawdaung and stay there.