Originally Posted by emcat
PS. If you are calling Mexico City, beware of the city code. The city code changed a few years back from 5 to 55, and local numbers also gained an extra 5. Local numbers are now 8 digits long, and 10 digits long with the city code added to them. That said, in some rare cases you might find numbers that are 8 digits long already with the city code and often calling 011+52+55+5xxx-xxxx will result in you reaching a different person than calling 011+52+5xxx-xxxx.
Hm, this "011+52+5xxx-xxxx" should not work since the last digit adjustment, some 3 years ago. That's when the first 5, which used to be the city code, was pushed onto the local number, and another 55 added for the city code. This "011+52+55+5xxx-xxxx" should be the only way to dial Mexico City (keep in mind that adding the 8th digit was done in order to increase the number of available phone numbers, and there are now xxxx-xxxx numbers that do not start with a 5).