International roaming is when you are using your SIM card from your home country abroad. It has proven to be usually very expensive, especially for data. Many cases have been reported where users come home facing a bill that equates to a month's salary or more. The solution is to use a local prepaid SIM card instead. That’s the raison d'être of this WIKI.
Can I buy a local prepaid SIM card in every country?
As an international tourist or visitor, you are free to buy a local prepaid SIM card all over the world with only a very few exceptions. These countries are mentioned in the respective articles and on our Blacklist where you won't be able to do so or don't get data. In our Greylistsome countries are included, where for various reasons you should think twice before buying a local SIM. In most of the 190 countries featured below, you are free to buy a local prepaid SIM card with data, although in some of them you have to show a travel document (like a national ID card, passport or if applicable a valid visa):
Which requirements must my device(s) meet? 
Your device needs to meet only three basic requirements to operate in a different country:
- it needs to be a GSM device
- it needs to be an unlocked device
- it needs to work on the frequencies employed in your destination country
For more info click on the pic on the right.
Data on SIM cards
When you have purchased a SIM card, topped it up with value, you may or may not have data right away. If you have, you will be on the standard or default data rate of the operator. This can also be quite expensive. In many cases, data is charged very high unless you purchase a data bundle. Click on the pic with the packages to learn more about default data rates and how to buy data packages.
How to find a good data rate?
First, you should check your home mobile provider, if international roaming at your destination is offered and at what price. This is for orientation mostly, how much you'll end up paying when you use international roaming. Then, you can look around further in your home country, if your provider or others give you a discounted rate for your destination.
International SIM cards in the all countries section can be an option, if you want to travel many countries in a short time. But you won’t save much using them. Our general recommendation to cut your roaming data cost is to buy a local SIM card in every country you visit especially if you want stay for a while or use a lot of data. This may sound a bit of a hassle but is straightforward in many cases and easy to do if you are aware of a few catches. In some countries it's possible to keep a SIM card active for a while after having left. If you expect to return, you should check the validity of your plan. Pick your destination in the list above and compare it with the international roaming rates you are offered.
In this glossary frequently used terms in the national chapters which may need more explanation are featured in detail. This is made for users who are not so familiar with the matter to get a basic knowledge. Just choose one subject you want to know more about and click on the pic below:
Here a Q&A troubleshooting will soon appear giving answers of the most common questions and issues when starting up.
Contributing to the wiki
This Wiki needs your help! We can't follow all developments and price updates in every country. That's why we welcome your contribution. If you are not sure how, check the How to edit this Wiki section first. For editing the articles, be aware that a couple of simple guidelines have been established.