List of reliable coaches/bus companies in Malaysia and Singapore

Here are some websites on coaches in KL to everywhere else in Malaysia including Singapore which might be useful to you.The ones mentioned are the main ones and more known for its reliability. Some are cheaper, some cost more due to their exclusiveness.

Tips:
1. If you are going to Malaysia from Singapore and back to Singapore, buy tickets separately as the tickets in Malaysia are cheaper due to conversion rate.
2. If you are going from Malaysia to Singapore and return, buy your return ticket in Malaysia as they are cheaper this way.
3.If you are travelling within Malaysia, you can buy your ticket practically anytime or check at your arrival point when you can get them. If you are travelling during Malaysian school holiday break it is unlikely you will get tickets.
4.My recommended busses would be Aeroline, Maraliner, Transtar, Plusliner.
http://www.nadi.com.my/
http://www.maraliner.com.my/
http://www.hasryexpress.com/
http://www.plusliner.com/
http://www.aeroline.com.my/ (ex Malaysia)
http://www.aeroline.com.sg/ (ex Singapore)
http://www.transtar.com.sg/
http://www.konsortium.com.sg/
http://www.kbes.com.my/
http://www.odysseynow.com.my/

http://www.srimaju.com/

http://www.gunungraya.com/
http://www.parkmayberhad.com/nice.html aka Nice Bus.

All info provided are served only as guide. Please refer to the operator for actual timings.