There are no service fees to be paid .. its a FREE service. However, while setting up your Twitter account, you will be asked to send a text message either to a LOCAL USA number (If you are in USA) or aninternational number to confirm whether you are the true owner of that phone number.. So this all depends where you are located and depends on your phone service plan.. Here's What Twitter.Com FAQ section says : "Twitter is in the United States...what if I'm not? Canadians should use 21212. We have international numbers for people outside of the US. If you're in the United Kingdom (UK) or most places in and around the European Union (EU) you can use: +44 7624 801423. This is our main international number currently, but if you'd like to see a local number for your area, Write us and let us know! " They are hinting that there may be a local number to your area, if you send them a note through this URL: http://help.twitter.com/index.php?pg=request Hope this helps