Chezza's debut solo single Fight For This Love from 2009 and Jepsen's smash hit from this year Call Me Maybe have become the second and third songs to achieve the milestone in 2012.
The Official Charts Company reports that Gotye and Kimbra's Somebody I Used To Know was the first track to reach the one million sales mark in the UK earlier this year.
Their achievement means that there have now been 125 million-sellers in the UK since the charts were launched in 1952, with the rise of downloads seeing an increase in the last ten years after there were only 76 million-sellers back in 2002.
OCC's managing director Martin Talbot stated: "Many congratulations are due to Carly Rae Jepsen and Cheryl Cole, who have joined Gotye to make it three million sellers this year.
"The fact that there has still only been 125 million sellers over the last 60 years indicates just quite how impressive a landmark it is to reach."
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