His single One Dance is now only two weeks away from breaking the record for the longest uninterrupted reign at the top of the chart.
Bryan Adams's single Everything I Do (I Do It For You), which held the number one spot for 16 weeks in 1991, is the current record holder.
The last single to notch up 15 weeks at number one was Wet Wet Wet's Love Is All Around, released in 1994.
One Dance owes much of its continued success to its popularity on streaming sites.
The song received 4.33 million streams this week - equivalent to 43,300 sales.
