A by-election for the Queensland state seat of Stafford will be held on July 19.
The poll was sparked by the resignation from parliament last month of outspoken former assistant health minister Chris Davis.
Premier Campbell Newman told parliament he consulted outgoing Governor Penelope Wensley on Wednesday night.
"The reason for choosing the 19th of July is that it's the first Saturday after the July school holidays," he said.
The ruling Liberal National Party holds Stafford, in Brisbane's north, by a 7.1 per cent margin.
But Labor candidate and facial surgeon Dr Anthony Lynham is considered the favourite, with the LNP yet to choose a contender following the close of nominations this week.
The by-election will be held five months after the LNP lost the Redcliffe by-election with a 17 per cent swing against it.
