The Colombo benchmark All Share Price Index closed 24.23 points higher at 7,548.23, up 0.32 percent.
The S&P SL20 closed 34.79 points higher at 4,204.87, up 0.83 percent.
Turnover was 3.83 billion rupees, up from 2.43 billion rupees a day earlier with 97 stocks closed positive against 114 negative.
Access Engineering closed 70 cents lower at 41.50 rupees with a massive off market transaction of 1.60 billion rupees changing hands at 40.10 rupees per share contributing 42 percent of the turnover while attracting most number of trades during the session.
The aggregate value of all off-the-floor deals represented 47 percent of the daily turnover.
Foreign investors bought 334.01 million rupees worth shares while selling 121.45 million rupees worth shares.
Dialog Axiata closed 90 cents higher at 14.00 rupees and Carson Cumberbatch closed 34.90 rupees higher at 474.90 rupees, contributing most to the index gain.