Somdev, who has 480 points, had reached the quarterfinals of the ATP Challenger event in Korea last week and that was enough to help him rise further up.
There was no change in the ranking of Yuki Bhambari, who has 480 points.
Mahesh Bhupathi (7) and Leander Paes (8) also found their rankings unchanged in the doubles list.
In the women's rankings, Sania Mirza managed to keep her 58th spot in the singles but dropped two places in doubles to 38th.
Somdev bows out of Seoul Challenger
Somdev, Prakash advance in Seoul ATP Challenger
Spotted: Leander Paes at Wimbledon 2008
Defeated Devvarman looks on bright side
Somdev qualifies for Legg Mason Classic