February:

Carnival
Massive carnival celebrations beginning with the running up the flagpole of  'het mooswief' (the greengrocerwoman).

June:

Jubileumfestival
Universiteit Maastricht 
June 9 – 11
Pop music, world music, theatre, cabaret

August:

Inkom
August 23th to August 26th
The INKOM is Maastricht's official student-introduction festival. The INKOM organises a broad range of activities, such as a mini 'Love-parade', cabaret, an open air film, and naturally, lots of parties!

Preuvenemint
Preuvenemint is a food festival held once every year in late August. Many of the Maastricht restaurants close down normal operations, reassembling their equipment and staff under tents in the Vrijthof. The restaurants offer dishes in exchange for Preuvenemint tickets purchased at the event.
The event typically runs from Thursday through Sunday, and is open from 2pm until 2am. Some restaurants stop serving food at the festival as early as 10pm, while others remain available until closing time.

September:

Parcours
Parcours is the yearly opening of the cultural season in Maastricht. The Parcours-weekend features free performances by artists all around the city. Theatre, music, and more.