The pair exchanged vows at a low-key ceremony at Kangaroo Valley Bush Retreat in New South Wales, reports the Australian Daily Telegraph.
They reportedly wanted to have their wedding outdoors with their friends and family.
Mitchell and Breeds announced their engagement in May 2012, after Mitchell had spent three months planning his proposal.
The couple first met in May 2009 shortly after Mitchell joined the cast of Home and Away.
Breeds left the soap as Ruby Buckton in August 2012, after the character had confessed to a serious crime.
Mitchell has also exited the show as Romeo Smith, but will remain on screen in Australia and the UK for some time as scenes are filmed months in advance.
Home and Away airs weekdays at 1.15pm and 6pm on Channel 5 in the UK, and weekdays at 7pm on Network Seven in Australia.