when was the last time the panthers were in the superbowl
In the 2016 season
Carolina Panthers

In the 2016 season, the Panthers regressed on their 15–1 record from 2015, posting a 6–10 record and a last-place finish in the NFC South, missing the playoffs for the first time since 2012, and losing the division title to the second-seeded Falcons, who went on to represent the NFC in Super Bowl LI.
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Carolina Panthers [SEP] 2010–2017
The Panthers also secured their third consecutive NFC South championship, as well as their first overall top-seeded playoff berth. In the 2015–16 playoffs, the Panthers defeated the Seattle Seahawks in the NFC Divisional playoffs, 31–24, after shutting them out in the first half, 31–0, and the Arizona Cardinals, 49–15, in the NFC Championship Game to advance to Super Bowl 50, their first Super Bowl appearance since the 2003 season. The Panthers lost a defensive struggle to the AFC champion Denver Broncos, 24–10. In the 2016 season, the Panthers regressed on their 15–1 record from 2015, posting a 6–10 record and a last-place finish in the NFC South, missing the playoffs for the first time since 2012, and losing the division title to the second-seeded Falcons, who went on to represent the NFC in Super Bowl LI.