The main All Share Price Index rose 0.54 percent (32.51 points) to 6,015.09, while the more liquid Milanka index rose 0.70 percent (36.25 points) to 5,226.11.
Turnover was 996 million rupees, according to stock exchange provisional figures.
Commercial Bank trades accounted for the bulk of the day's turnover, generating almost 796 million rupees, with over 7.9 million shares changing hands.
There were four crossings or off-market private deals of 7,625,200 Commercial Bank shares, all at 100 rupees each.
The stock closed at 100.50 rupees, up 40 cents, after hitting a high of 101.30.
Lanka Securities said the seller was a foreign investor and the buyer was believed to be a local party.
"Foreign participation stood at 41.7 percent of total market activity and at the end of the day foreign investors were net sellers with a net foreign outflow of 788.2 million rupees."
Index heavyweight John Keells Holdings closed up 1.30 rupees at 171.50.
SMB Leasing non-voting shares led the day's gainers, closing at 80 cents, up 10 cents, with 382,500 shares changing hands, followed by Hayleys Exports, which rose 3.50 to end at 37.50 rupees on just one transaction of 100 shares.
Environmental Resources Investments and HVA Foods, whose prices had been highly volatile after they drew the interest of speculators, were the two most actively traded stocks Tuesday.
ERI closed flat at 39.70 rupees while HVA Foods ended 10 cents lower at 37 rupees.