Almost every town in Mexico has an "oficina de correos" (post office) where stamps can be purchased. They are usually open Saturday mornings as well as long hours Monday to Friday.

There is still only few competition among the telecommunication companies. In effect, Telmex has today almost a monopoly. Local calls are cheap. However, international and national calls are very expensive, and will depend on the place and the time of the call.

Internet telephony (calls carried through an Internet server line instead of a phone line) has appeared at some Internet Cafés in Mexico City, nonetheless, not yet in other cities. It will likely spread around the country. It's a lot cheaper that regular phone calls. In effect, at around US$ 0.35 p/minute to the USA or US$0.50 p/minute to Canada or Europe.

Meanwhile, telephone and prepaid cards can be used. Be careful with collect calls, because it could cost the receiving party much more that if they call you.