Regional viewers will lose high-definition channel 9HD and the lifestyle channel 9Life when Southern Cross Austereo switches to showing the Nine suite of channels from Friday July 1.

The regional broadcaster says it won't be able to upgrade its transmission equipment in time for viewers to be able to watch the third rugby league State of Origin match in high definition.

At the end of the month Southern Cross Austereo will drop its "Southern Cross Ten" branding and begin carrying Nine's name and programs as rival WIN Network swaps to showing Network Ten content.

Nine's programs are currently broadcast in regional Victoria, Queensland and southern NSW on WIN channels 8 and 80 to 84.

But from July 1 regional viewers will need to flip over to channels 5 and 50 to 54 on their remote controls to find such programs as The Voice, Millionaire Hot Seat, Love Child and 60 Minutes.

Southern Cross Austereo's relay of Nine's primary channel will be found in standard-definition on channels 5 and 51.

The 9Gem channel will be on 52 and 9GO! will be on 53.

But 9HD - a high-definition simulcast of Nine's main channel, including live NRL and Origin telecasts - will not be available from July 1.

"The equipment needed for Southern Cross Austereo to be able to broadcast the Nine primary channel in HD has been ordered from Europe," Southern Cross Austereo said.

"As soon as it arrives and is installed, we will start broadcasting 9HD."

The broadcaster said 9HD was expected to be on-air on channel 50 "by mid-August at the latest".

The equipment delay will also affect 9Life, which will be off-air from the July 1 switch-over until "mid-August" when it re-appears on channel 54.

Regional viewers will only be able to watch 9Life streamed via the 9Now website.

WIN launched 9Life and Nine's HD channel in regional markets in March.

The first-run international lifestyle and reality programming of 9Life, including such shows as House Hunters, Beachfront Bargain and Real Housewives, has made the channel a surprise ratings success.

WIN's move into HD this year was welcomed by regional viewers with big-screen, high-definition TV sets, especially armchair sports fans.

WIN is expected to carry TenHD from July 1, which means programs such as Masterchef, Big Bash cricket and The Project will be available in high definition.

WIN is expected to broadcast Ten's programs on channels 8 and 80 to 84.

As they prepare to swap their respective 30-year program supply agreements with Nine and Ten, WIN and Southern Cross Austereo are already promoting shows that haven't changed channels yet.

WIN confirmed this week that season six of the much-loved Asher Keddie drama series Offspring would premiere on Southern Cross Ten on Wednesday June 29 but then switch over to WIN from its second episode on July 6.

Southern Cross Austereo has launched an "information campaign" on its regional radio stations, plus the website nineon5.com.au, to inform viewers of the changes.

Areas affected by the channel changes: the ACT and southern NSW centres like Wollongong, Wagga Wagga, Orange, Dubbo and the South Coast; Victorian regions like Albury/Wodonga, Shepparton, Ballarat, Bendigo and Gippsland; and regional Queensland centres Cairns, Townsville, Mackay, Rockhampton, Bundaberg, Sunshine Coast and Toowoomba.

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