[1][2][3] Public utility services use short phone numbers (usually three digits), always starting with 1.
901 to 909 have been reserved for automated system of national collect calls (see below) since 1982 and cannot be used as local initial digits.
Even shorter numbers used to exist in previous decades, especially in small towns and before direct distance dialing became universal.
Until 2008, the initial digit 6 was used for landlines in some parts of São Paulo and neighbouring cities in area code 11, but Anatel required that 6 be released for mobile use.
The use of the initial digit 2 is occasional except in Greater São Paulo and the state of Rio de Janeiro.
However, all local landline telephone companies offer on-line directory inquiries on their Web sites.
Mobile phone numbers in Brazil are assigned the same geographic area codes as fixed lines, according to the subscriber's place of residence or most frequent use.
Now GSM is universally adopted by Brazilian mobile operators and, combined with number portability and the inclusion of a ninth digit to the left (see below), this distinction is no longer observed or meaningful.
Overlays and extra area codes were considered, but deemed confusing and impractical for local conditions.
So, on 10 December 2010, ANATEL announced the inclusion of a ninth digit (in the format 9nnnn-nnnn) to mobile phone numbers used in the São Paulo metropolitan region (area code 11).
[8] Telecom providers would have 24 months to implement the ability to dial a new digit to the left of all cell phone numbers of area code 11,[8] but the measure ended up being implemented a few months ahead of that initial schedule, on 29 July 2012.
[9] To standardize the mobile numbering plan in Brazil, ANATEL started gradually rolling out the change to nine digits in other area codes and states as well.
Despite this fact, mobile phones registered outside the 11–19 (São Paulo), 21, 22, 24 (Rio de Janeiro) and 27–28 (Espírito Santo) areas are usually displayed on WhatsApp (widely used by Brazilians to send text, voice and video messages due to the privileged access granted by mobile operators, in contrast to the assumption of network neutrality present in the Marco Civil da Internet) with the old 8-digit number.
Usually a call to 190 (military police) describing an emergency with a non-criminal nature will be redirected to the proper number or provide assistance if they are qualified to (as in cases of choking children).
By law, 136 is printed on the packaging of all tobacco products sold in Brazil, so it is usually thought to be just a smoking cessation help hotline.
That hotline does exist and can be accessed by this number, but 136 is actually a more comprehensive contact channel between citizens and the Ministry of Health.
The law was made because of the large number of foreign tourists expected for the 2014 FIFA World Cup and the 2016 Summer Olympics in Rio de Janeiro, so the redirecting numbers were initially reachable only from the 12 World Cup host cities, but later the change was extended to the entire country.
For example, in many cities, such as São Paulo,[12] one can get information, make requests and complaints about most services and issues with the municipal administration by dialing 156.
Regional utilities for services such as electricity and water supply may also have short access numbers starting with 1.
Landline telephone companies' customer service numbers have been normalized as 103, followed by a two-digit code.
For cable and satellite television operators, the number is 106, followed by a two-digit code (e.g., 106-21 for Net and 106-11 for SKY Brasil).
Due to persistence of old habits from the time when carrier codes were not used (see below), the format (0aa) nnnn-nnnn is still commonly seen, but this usage is discouraged, since it may confuse customers when actually calling, despite the mobile carriers give the option to complete the call with the old dialing (0aa) nnnn-nnnn with their own code in the configuration of the GSM/UMTS/HSPA/LTE SIM cards sold in the country.
Because of that, sometimes long-distance phone numbers are written down as (0xxaa) nnnn-nnnn, with two actual letters x as placeholders, which the caller will replace by a carrier code.
For example, to call the mobile number 98999-6666 registered in Ribeirão Preto region (area code 16) outside of this area using the long-distance carrier Vivo (selection code 15), one would dial 9 0 15 16 98999 6666. International collect calls, for countries for which it is available, are not automated and must be placed through Embratel's international operator, dialing 0800-703-2111.
As a result, these numbers are associated with state capitals and their metropolitan regions or the largest city in the area.
For example, to call the number 3210-9876 in São Paulo (area code 11) from the United States, one would dial 011 55 11 3210 9876.
Fixed-line customers can keep their numbers when moving their address and/or when switching telephone companies within the same municipality, and mobile lines customers can keep their numbers provided they stay within the same local area (i.e., the portion of the area code where calls are charged as local).