Big Day is a Polish band that was formed in July 1992 in Olsztyn. They played their first concert on August 30, 1992 and on that day the group celebrates their birthday. In December 1992, they made their first professional recordings, which were used as promotional material presented to radio stations and record companies. Despite several changes in the line-up of the group since the beginning in the band are Ania Zalewska and Marcin Ciurapiński - Big Day's frontmen.
The band is described as pop rock of the tradition of the 60s, and British guitar music from the early 90's. But with time Big Day showed that they have their own style.