90th season of top-tier Swiss football
Statistics of the Swiss National League in the 1986–87 football season, both Nationalliga A and Nationalliga B.
Overview.
There were 32 member clubs in the Swiss Football Association (ASF/SFV), divided into two tiers of 16 teams each. At the end of the season there would be changes in the ASF/SFV and to the format of the league. These modifications included increassing the number of members in the association by four clubs. It had also been decided to reduce the size of the top tier NLA by four teams and to inrease the size of the second-tier NLB by eight teams. 
In both divisions the teams played a double round-robin to decide their table positions. The Swiss champions would qualify for the 1987–88 European Cup, the runners-up and third placed team would qualify for the 1987–88 UEFA Cup. The last two placed teams in the NLA would be directly relegated. The four teams in eleventh to fourteenth position would compete a play-out round with the top four teams of the NLB to decide the last two slots in next season's NLA. The last four teams in the NLB would compete a play-off round against the top eight team of the 1. Liga to decide the final eight slots in next season's NLB.
Nationalliga A.
The first round was played on 9 August 1986. There was to be a winter break between 29 November and 28 February 1987. The season was completed on 12 June 1987.
Final league table.
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Nationalliga B.
The first round was played on 9 August 1986. There was to be a winter break between 30 November and 7 March 1987. The season was completed on 13 June 1987.
Final league table.
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Promotion/relegation play-off NLA/NLB.
The four teams in eleventh to fourteenth position in the NLA competed a two-legged play-off round with the top four teams of the NLB to decide the last two slots in next season's NLA. The qualification games were played on 20 and 23 June and the finals on 27 and 30 June.