Internacional returned to Brazil's top division football after a goalless away draw against fellow promotion aspirants Oeste.
The result on Tuesday left Internacional with 65 points with two matches remaining, guaranteeing them a top-four finish in Serie B. Oeste were sixth, two points shy of the promotion places, reports Xinhua news agency.
Despite their impressive 2017 campaign, Internacional remain four points behind leaders America-MG, who secured their return to Serie A on Sunday.
One of Brazil's most traditional clubs, Internacional are three-time Serie A champions and two-time winners of the Copa Libertadores, South America's top club competition.
The Porto Alegre side were last year relegated for the first time since the start of the national competition in 1971.