Five is to take the final position in the UK DTT multiplex set aside for high definition broadcasts.
Ofcom said it had made a provisional decision to reserve capacity for the RTL-owned broadcaster, providing a number of criteria are met by the end of the year.
The decision follows a tender process for the fourth and final slot that had pitched Five against a combined bid from Channel 4 and S4C. It means that Five will join HD channels from the BBC, ITV and Channel 4/S4C when the HD multiplex goes live in the North West region this autumn.
Multiplex B is being reorganised to allow for the introduction of the HD multiplex as each region goes through analogue switch-off. Ofcom is also in discussions with the BBC to allow temporary HD transmissions under temporary frequency assignments until the completion of ASO in 2012.