Singtel: $0.28/mins $0.10/sms
M1: $0.05/sms (1) $0.05/mins(超级非繁忙时段:21pm-09am and Sunday)
(2) $0.10/mins(非繁忙时段: 19-21pm)
(3) $0.20/mins(other)
Starhub: 接电话不需付费，好像是短信$0.10/sms,电话$0.20/mins（信号比较差）

大致是这样的，仅作参考...