This season featured only three teams that failed to make the previous season's postseason. The New York Giants, who were eliminated on the final day of the 1988 season, rebounded to win a division title, while the Denver Broncos and Pittsburgh Steelers recovered from disappointing seasons.

For this year only, the starting times for the Conference Championship Games were changed from the then-customary 12:30 p.m. and 4:00 p.m. EST to 1:30 p.m. and 5:00 p.m. EST. This was to accommodate the fact that the Denver Broncos and San Francisco 49ers hosted the AFC and NFC Championship Games in the Mountain Time Zone and Pacific Time Zone, respectively—thus avoiding a locally played game at 9:30 a.m. PST or 10:30 a.m. MST.

Within each conference, the three division winners and the two wild card teams (the top two non-division winners with the best overall regular season records) qualified for the playoffs. The three division winners were seeded 1 through 3 based on their overall won-lost-tied record, and the wild card teams were seeded 4 and 5. The NFL did not use a fixed bracket playoff system. In the first round, dubbed the wild-card playoffs or wild-card weekend, the fourth seed wild card hosted the fifth seed. All three division winners from each conference then received a bye in the first round. The second round, the divisional playoffs, had a restriction where two teams from the same division could not meet: the surviving wild card team visited the division champion outside its own division that had the higher seed, and the remaining two teams from that conference played each other. The two surviving teams from each conference's divisional playoff games then meet in the respective AFC and NFC Conference Championship games, hosted by the higher seed. Although the Super Bowl, the fourth and final round of the playoffs, was played at a neutral site, the designated home team was based on an annual rotation by conference.

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