Overview of Oi
Oi is a long-standing Brazilian telecom operator. It grew out of Telemar, the largest regional company in the 1998 privatization of Brazilian telecommunications, covering 64% of Brazil's territory. The Oi brand was created in 2001, at first for mobile service. Oi was once Brazil's largest fixed-line group, the third-largest fixed-broadband provider, and the fourth-largest mobile operator. In 2020 it sold its mobile assets to Vivo, Claro, and TIM. A few months after it completed its first bankruptcy restructuring in December 2022, it filed for protection again in March 2023. In November 2025 a Rio de Janeiro court declared Oi bankrupt. A trustee took over the company. ANATEL confirmed that telecom services continue during the transition.
Before the restructuring, Oi offered M2M connectivity and enterprise leased lines. Its assets and business are now uncertain. For a new IoT deployment, Vivo, Claro, and TIM Brasil are the more stable choices.
Oi facts
- Founded: 1998 (Telemar); Oi brand created in 2001
- Headquarters: Rio de Janeiro, Brazil
- Former position: Brazil's largest fixed-line group, third-largest broadband provider, fourth-largest mobile operator
- 2020: Mobile assets sold to Vivo, Claro, and TIM
- First bankruptcy: Filed in June 2016; restructuring completed in December 2022
- Second bankruptcy: Filed again in March 2023, with debt of about BRL 29 billion
- Bankruptcy order: Court declared bankruptcy in November 2025, with debt of about BRL 1.7 billion
- Now: Run by the trustee; services are still operating
History and milestones
Telemar, Oi's predecessor, was bought in the 1998 privatization by consortia that included Andrade Gutierrez. In May 2009 Oi bought Brasil Telecom, which covered 30% of Brazil's territory, for nearly BRL 6 billion. That deal was later described as the start of the debt build-up. In June 2016 Oi filed for the largest bankruptcy protection in Brazilian history, with debts far above any earlier case. After more than six years of restructuring, it completed that first proceeding in December 2022.
In March 2023, only months later, Oi filed for protection again, with about BRL 29 billion owed to creditors. In April 2024 creditors approved a new plan, with 79.87% in favour, including USD 655 million of new funding and a USD 135.8 million bridge loan. In November 2025, after Oi failed to carry out the 2024 plan, the court declared it bankrupt. Thirty-six investors face a total loss. ANATEL confirmed that telecom services would be kept up during the transition.
Earlier services, for reference
Before it sold the mobile assets, Oi offered fixed voice, broadband, pay-TV, and mobile service. For IoT it offered M2M SIMs, dedicated APNs, and enterprise lines. The asset base is now much smaller. Mobile has been sold. Fixed and broadband service is still run by the trustee.
Notes for IoT deployment
- New projects: Vivo, Claro, and TIM Brasil are the steadier operators to start with
- Existing Oi connections: Review a move to another operator if a service break would be a problem
- Fixed assets: Oi's fixed network may change hands in a later restructuring or sale
- Regulator: ANATEL requires telecom service to continue through the bankruptcy transition, so short-term use can continue