Summary
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Anatel will require authentication of calls made by those who make more than 500,000 calls per month, starting in November 2025.
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The measure mainly aims to combat spoofing and improve transparency in telemarketing calls.
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The new standards involve 28 telecommunications operators.
In November, telecommunications operators will have to authenticate calls made by “large callers”, which are individuals or organizations that make more than 500,000 calls per month. This is a measure by the National Telecommunications Agency (Anatel) to combat the problem of abusive calls that torments Brazilians so much.
This obligation is part of the rules that Anatel published in this Monday’s edition (20/10) of the Official Gazette of the Union. They come into force on November 1st and are valid until October 31st, 2028.
The authentication process consists of a procedure that verifies whether the call is made from a number that, in fact, belongs to the natural or legal person making the call. This measure aims to curb practices such as spoofing, used to mask fraudulent calls pretending to be legitimate organizations.
When authentication is done, confirming that the call is legitimate, the person receiving the call will be able to see a check symbol next to the calling number.
The rules established by Anatel also determine that large callers who do not participate in the authentication process are notified.
Any individual or legal entity that is notified and does not adopt the authentication system within 30 days will be prevented from making new calls.
The new rules are valid for individuals or organizations that make more than 500,000 calls per month, and are waived for those that do not exceed this number for three consecutive months.
The calculation considers the sum of calls made by all telephone numbers registered with the individual’s CPF or linked to the organization’s CNPJs.
Anatel may exempt individuals or legal entities from authentication who prove that the calls made are not related to “massive teleservices”.


Which operators do Anatel’s new rules apply to?
Anatel’s determinations involve 28 fixed, mobile or voice over IP companies. All must implement the verification system. They are:
- Agera Telecom
- Agil Telecom
- Algar Telecom
- America Net (Vero)
- Baldussi Telecom
- Big Telco
- Brasilfone
- Brisanet
- Of course
- Computer
- EAÍ Telecom
- Flux Technology
- Always Talk More
- GT Group
- Today Telecom
- IDT Brasil (net2phone)
- Infinitus Brasil Telecommunications
- Itelco
- JAS Telecommunications
- Neo Telecom
- Hey
- Sercomtel
- Surf Telecom
- Telefônica Brasil (Vivo)
- Telexperts (Telecall)
- TIM
- National TVN
- Vonex Telecommunications
This is one of the measures adopted by Anatel in return for the end of the mandatory prefix 0303 in telemarketing calls. This is a complementary initiative to the Verified Origin program, which can inform the user of the reason for the call and the details of the company making the call, but is not mandatory.
Source: https://tecnoblog.net/noticias/regras-da-anatel-para-grandes-chamadores-comecam-em-novembro/
