The phone was released globally at the end of September this year and sold three million units in the first month. The 5.5 in 'phablet' then went on to ship another 2 million since November 2.
Prior to the Galaxy Note II, Samsung's Galaxy SIII had success with 30 million channel sales five months after its release.
"The GALAXY S III continues to be a runaway favorite with customers around the world. Meeting this sales milestone in five months sets another record for Samsung, and we are extremely proud and yet motivated to continue to provide our customers with products that they love," said JK Shin, Samsung's mobile chief, in a statement. "On behalf of Samsung Mobile, I appreciate millions of customers around the world that have chosen the Samsung GALAXY S III."
Samsung Galaxy SIII was dubbed the world's best selling smartphone model in Q3 2012 by Strategy Analytics.
The phone surpassed the number of shipments of Apple's iPhone 4s.
Analysts said the phone was propelled to the top spot with its large touchscreen and vast distribution across many countries.
"Samsung's Galaxy S3 smartphone model shipped 18.0 million units worldwide during the third quarter of 2012. The Galaxy S3 captured and impressive 11 percent share of all smartphones shipped globally and it has become the world's best selling smartphone model for the first time ever," said Neil Mawston, executive director at Strategy Analytics. "Apple shipped an estimated 16.2 million iPhone 4S units worldwide for second plates as consumers temporarily held off purchases in anticipation of a widely expected iPhone 5 upgrade at the end of the quarter."
However, Mawston said the Samsung Galaxy S3's reign may be shortlived as the iPhone 5 will prove to be tough competition.
"Apple's iPhone 5 has gotten off to a solid start already with an estimated 6.0 million units shipped globally during Q3 2012," added Mawston. "We expect the new iPhone 5 to out-ship Samsung's Galaxy S3 in the coming fourth quarter of 2012 and Apple should soon reclaim the title of the world's most popular smartphone model.
Samsung predicts the Galaxy Note II will bring in around 20 million sales, which if sold at this rate could outdo the Galaxy note's record of 10 million units sold in 9 months.
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