Vince, who’s skippered the side since 2015, will continue to lead Hampshire in limited over matches.
But Australian international Bailey – who resigned this season – takes over as captain for County Championship games.
Giles White, Hampshire director of cricket, says the move will allow both players to focus on their own games whilst still contributing with their leadership skills.
White said: ‘We are fortunate to have two excellent captains within the squad and a split between the formats seems a sensible option for us.
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‘James will captain the white ball teams and George the Championship side.
‘This will allow them to channel their focus in the different formats which should benefit the squad as it looks to compete across all formats.’
Bailey’s first competitive match as four-day skipper will Hampshire’s match at Essex on May 19.