Option 1: International Roaming
Does your plan allow International roaming? Check with your phone operator if you can use your phone in Southeast Asia, and what services you can use while you’re roaming. If you’re a T-Mobile user, you can read T-Mobile’s International Roaming Overview. If your phone uses AT&T’s network, you can find the info you need at their Roaming Packages page.
Be warned: it will cost you a lot more to make or receive phone calls while roaming abroad, assuming your phone does work at all, so don’t be surprised if your phone bill has a few extra zeroes tacked on when you get back.
PROS: Use your own cellphone and get billed on the same account you use at home
CONS: Expensive, limited coverage
Option 2: Unlocked Phone, Prepaid SIM
If you have a quad-band GSM phone, but you think you’re being stiffed by your provider on your roaming fees, you might also consider buying a prepaid SIM card in your destination country.
The SIM (Subscriber Identification Module or Subscriber Identity Module) card is unique to GSM phones, a transferable "smart card" that holds your phone settings and authorizes your phone to access the local network. The card can be switched from one phone to another: the phone simply assumes the new SIM card’s identity, phone number and all.
Prepaid SIM cards can be bought in every Southeast Asian country with GSM cellular service: simply buy a SIM pack, insert the SIM card into your phone (assuming it’s unlocked – more on that later), and you’re ready to go.
Prepaid SIM cards have a “load”, or balance, included in the package. This balance is deducted as you make calls on the new SIM; the deductions depend on the rates included with the SIM card you purchased. You can “reload” or “top up” your balance with scratch cards from the SIM card’s own brand, which can usually be found at certain convenience stores or sidewalk stalls.
Before you can use a local SIM card, though, you have to check if your phone is “locked” with your current provider. Service providers often “lock” handsets, permitting only their SIM cards to use the phone. This is done to prevent users from transferring their subsidized handsets to competing carriers. However, if you’re a longtime subscriber, your carrier might provide an unlock code if you ask nicely enough.
Check with the SIM card provider’s homepage for each card’s available services and call costs:
- Cambodia: Hello or CamGSM
- Indonesia: Indosat, Telkomsel, or Excelcom
- Malaysia: Celcom, DiGi, or Maxis
- Philippines: Globe, Smart, or Digitel/Sun Cellular
- Singapore: M1, Singtel, or Starhub
- Thailand: True Move, AIS, or DTAC
- Vietnam: Mobifone, Vinaphone, or Viettel Mobile
PROS: Pay local rates for local calls, saving up to 80%
CONS: You’ll use a different cellphone number
