Which is the Best International
How to choose the best SIM and phone service option for your phone
when traveling internationally
Choose whichever of seven different types of SIM card and
its associated phone service works best for you on your
travels and simply swap it (them) in and out of your GSM
phone as you travel from home to other countries.
9 of an 10 part series - click for Parts
It is important to choose the
right SIM and service for your phone when traveling
internationally. A wrong choice at best may cost you a
great deal more money for the calls you make and receive, and at
worst, may mean that you have limited or even no service at all
while away from your home country.
This information will help you
understand the issues offered by various different SIM providers
and make the best choice for your situation and circumstance.
Other articles in this series
about international cell phone service
are also helpful.
Introduction - SIMs and Service
With a GSM type phone (see
Step One below) your phone itself has no 'identity' or
associated phone number. All this is kept within the user
swappable SIM card that you plug into the phone. You
change your SIM and this changes your phone's service provider and
phone number. Think of a SIM as a regular telephone line,
and your cell phone as a regular phone - a regular phone can
work on any telephone line, and assumes the number associated
with the phone line. The same concept applies (more or
less) to GSM type cellphones and the SIMs they connect through.
This flexibility works
greatly to your advantage when traveling outside your home
wireless provider's network. No longer do you need to
suffer very high international phone call costs, instead you can
mix and match SIMs and their associated services and costs as
you travel from country to country so as to get the best value
Step One - Confirm your phone
Before you start to consider
different SIM and service options for traveling out of your
home country, you first need to confirm the phone you plan to
use will work in the countries you plan to visit.
Most countries use GSM type
phone service, and there are four different frequency bands
variously used by different countries. Here is
about which countries use which GSM frequency bands so you
can make sure your GSM phone has the necessary bands to work in the countries you visit.
In the US, the two main GSM
based phone companies are AT&T/Cingular and T-mobile.
Some phones use a different
type of service such as CDMA (this is used by Sprint and Verizon
in the US, for example). Not many other countries have
CDMA based cell phone service, and if you're traveling outside
North America, you will need to buy an unlocked GSM phone
to use on your travels. We sell
some ourselves, and another
reputable supplier of unlocked GSM phones is
Step Two - Confirm your GSM
phone is unlocked
If you acquired your phone
when signing a contract for phone service with your wireless
provider, the chances are it is probably 'locked' and will only
work with the SIM your current wireless provider gave you.
If you want to use a
different SIM in a locked phone, the phone will need to be
electronically unlocked before it will accept a different SIM.
How to tell if your phone is
locked or not
The easiest way to tell is
to put a SIM from a different wireless service in the phone.
For example, if you have a Cingular phone, try putting in an
older AT&T SIM or a T-Mobile SIM (or of course any other SIM
from any other wireless company, anywhere in the world).
Chances are someone else at work has a phone with a different
SIM that you could borrow for the quick minute this takes.
If the phone is locked, it
will display an error message of some type when you turn it on
with the other SIM installed (typical messages include 'Contact
Service Provider' or 'Enter Subsidy Code' or 'Invalid SIM').
If the phone is unlocked, it
will either start up normally, or perhaps will start up and then
say 'Unregistered SIM' or 'No Service' (if using a foreign or
How to unlock a locked GSM
The first thing to do is to
ask your current wireless provider if they'll unlock your phone
for you, for free. T-mobile will generally do this if your
account is in good standing and you've been a subscriber for
more than three months. AT&T/Cingular is unpredictable -
sometimes they'll unlock your phone, but often they won't.
Their current (Nov 07) policy seems to be that they'll unlock
your phone once your one or two year contract has been
If your cell phone company
refuses to unlock your phone, don't panic. Many companies offer
unlocking services, including, ahem, ourselves. You'll see
links in the 'Related Articles' box on the top right of this
article to pages about unlocking various different brands of
Step Three - International
Charger or Adapter
Now that you have a phone
that you've confirmed will work in the countries you're
visiting, and unlocked to accept whatever SIMs you
choose to use, there's one more thing just to quickly confirm
before moving on to the issue of which SIM or SIMs you should
Is your charger multi-voltage
Just make sure your phone
charger is multi-voltage so that it will work with the voltage
of the countries you are visiting. North America uses
110V, most other countries use somewhere between 220V and 250V.
Most - but not all - phone chargers these days are
multi-voltage, but quickly read the label to confirm it says
something like 100V-250V or maybe 110V/220V to indicate it is
If the charger is not
multi-voltage and you're going to a country with different
voltage to your home country, you'll need to either get a
multi-voltage charger or a transformer to change the voltage you
feed into the charger. The better choice is just to get a
second multi-voltage charger - they are not very expensive and
are very convenient.
has a wide range of
chargers at low prices.
If you're traveling to a
country with different voltage (and even if you're not), the
chances are that it might use a different type of plug to fit
into the wall sockets. Get a set of plug adapters from a
local electronics store (such as Radio Shack in the US).
These are lightweight and inexpensive.
Bad News : There's No
Such Thing as a Single Best Solution for International Phone
If there was a single best
solution for everyone's needs while they travel internationally,
this article would be very much shorter and simpler!
this is not the case, and so you need to balance the different
factors that make up how you'll be using your phone
internationally to find which of the many different approaches
is the best compromise between cost and convenience.
A person who travels very
regularly and uses their phone extensively would probably end up
choosing to buy individual prepaid SIMs for each country they
regularly visit; a person who makes only occasional journeys and
expects to use their phone very seldom would probably choose a
Mobal SIM or to simply use international roaming with their home
If you fall somewhere
between these two extremes, or if you have special needs, then
and review the summary table and the explanatory notes that follow.
We've compared ten
different service options for your international phone service.
Here's a quick summary of the strengths and weaknesses of each
Here's a quick summary of the strengths and weaknesses of each
option. (This will pop up in a new window.)
The next table lists
detailed features and rates for each of the ten different
options, so you can better understand the strengths and
weaknesses of each option and how it would relate to your own
Detailed feature and rate analysis for each option (This
will pop up in a new window.)
Traveling with a cell phone
is getting easier and more affordable. No longer do you
need to pay many dollars a minute to send and receive calls -
the latest international SIMs and their associated calling plans
will often give you unlimited free incoming calls, and outbound
calls for between 50¢ and $1 per minute.
Use the two tables above to
match your own travel and phone usage patterns to the best SIM
and service option.
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19 Jan 2007, last update
15 Sep 2011
You may freely reproduce or distribute this article for noncommercial purposes as long as you give credit to me as original writer.