Staff who chose not to wear a onesie to work were ''fined'' $5 and others made a gold coin donation.
Council chief executive Stuart Duncan, dressed as the Nintendo character Luigi, second from right, said events such as this week's ''onesie day'' were important for staff morale ''as well as raising funds for a great local cause''.
The council had 56 employees and issued nine fines for not wearing a onesie this week, a council spokeswoman said.
''All staff made very generous donations regardless of whether they wore onesies or were fined,'' she said.