Choir president Sue Bragg, of Dunedin, said the celebration started with a workshop at All Saints Hall, in Cumberland St, on Saturday afternoon, featuring guest conductor Sue Mepham.
The choir performed a concert at All Saints Church on Saturday night.
Included on the programme was Daydream Believer by The Monkees and That's What Friends Are For by Dionne Warwick.
The all-female choir had more than 20 active members. The oldest was in her 70s and the youngest performer was piano accompanist Ihlara McIndoe (16).
''A good, healthy range,'' Mrs Bragg said.
Mrs Bragg said future prospects were ''looking great'' for the choir.
''We've got a really strong group of women who love singing.''
Choir founder Efie Cockburn, of Cromwell, said she started the Melrose Singers as a mixed-gender youth choir in 1974.
''I was a singing teacher and quite a few pupils were such good singers I thought they would combine well into a choir.''
Mrs Cockburn said singing in harmony with a ''togetherness'' took a lot of practice.
''You don't want any one person sticking out. It's as one voice.''