The international telephone code for Guatemala is 502. There is no area code. All telephone numbers have eight digits. On 18 September 2004, the telephone system was changed from seven to eight digits, and there is a system for adding certain digits to the beginning of seven-digit numbers (description WTNG.info.
The telephone system is not great, but it works. Tourists can call abroad from call centres where you pay by the minute. It is also easy to buy a phone card to use on public phones. The phones do not accept money. So to use a public phone on the street, you have to buy a phone card. Generally, the cost of a 10-minute call to North America is about 8 quetzals. Mobile phones are quite cheap and calls to the US can cost as little as $0.08 per minute. If you plan to stay and use the phone for a while, consider buying a cheap prepaid phone. Nationwide wireless internet access for laptops is also offered as a service by some companies. Telefónica offers good coverage with its PCMCIA EV-DO cards.
The postal system is traditionally unreliable, but your postcards usually get through. A stamp for Europe costs Q5. However, there are many other alternatives to the federal post office that are reliable, although often a little more expensive.
Internet access is widely available. Even most remote areas have some kind of internet access. Many larger areas also have WiFi. All Pizza and Chicken Camperos restaurants (of which there are many) offer free WiFi, as do many other restaurants and cafés. Some hotels also offer computer banks with internet access. Just ask and you will eventually find some kind of free access.
Mobile Internet access (3G/GPRS)
If you have an internet-capable mobile phone (iPhone, Google Android, Nokia N95 etc.) or a USB stick for your laptop, all you need to do is get a local SIM card (approx. 25 euros) and you can take advantage of the prepaid access rates, which are usually offered in hourly, daily or weekly increments.
Anecdote: When I was in Guatemala in May 2010, I bought a SIM card from TIGO Guatemala and a day or two later I automatically received an SMS offering me 30 days of free internet access without having to do anything, which was variable in its reliability but still very useful. With a programme like PDANet, you can create a mini-WiFi network that follows you wherever you go. I looked it up and apparently the normal way to activate the internet after making the correct configuration settings was to send the SMS message “WAP” to shortcode 805, but I didn’t have to do that. The APN (Access Point Name) was internet.tigo.gt.