There were 32 member clubs in the Swiss Football Association (ASF/SFV), divided into two tiers of 16 teams each.
These modifications included increassing the number of members in the association by four clubs.
In both divisions the teams played a double round-robin to decide their table positions.
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.
Basel win in the penalty shoot-out and continue to the finals.
Vevey Sports are relegated to 1987–88 Nationalliga B. Wettingen win 4–0 on aggregate and continue to the finals.
Wettingen are relegated to 1987–88 Nationalliga B Aarau win 5–1 on aggregate and remain in the NLA.
BSC Old Boys win 6–1 on aggregate and are promoted to the 1987–88 Nationalliga B. SC Kriens are relegated to the 1987–88 Swiss 1.