When visiting Greenland you will find no telephone booths. You can call from hotels. Almost every post office also have the service with public payphones, from where you can call anywhere in the world.
In Greenland you will find a developed telecommunication network, and the mobile phone is used widespread. You will find well roaming agreements exists for some international mobile companies.
Mobile phones can also be hired at TELE Greenland shops in all towns. (A deposit is required.). The mobile phone system in Greenland is GSM 900/1800, and nearly all inhabited areas are covered. MMS/GPRS data network and mobile broadband (3G) is also available. You will also find many post offices selling mobile phones and calling cards.
The country code for Greenland is 299. To make international calls out of Greenland, dial 00 and then the country code + phone number.