Natalie Bassingthwaighte will marry her long-time partner Cameron McGlinchy on December 3.

The 35-year-old star and her former Rogue Traders bandmate will tie the knot in a "fun family affair" at a mystery Melbourne location with their daughter Harper, who turns one next week, by their side.

Bassingthwaighte, who will finish up her stint as a judge on Seven's The X Factor just days before the nuptials, has chosen a gown by leading Australian wedding design team J'Aton for the ceremony.