The All Share Price Index fell 0.55 percent (13.29 points) to end at 2,420.06 while the more liquid Milanka was down 1.
11 percent (32.59 points) to 2,913.77. Turnover was 530 million rupees.
"Foreigners were heavier on the selling side bringing a net outflow of 288.91 million rupees," Bartleet Mallory Stockbrokers said.
John Keells Holdings ended 75 cents weaker at 108.
25 rupees with just over two million shares traded.
Bartleet Mallory Stockbrokers said the day saw four crossings on JKH at a flat price of 110 rupees, making the largest contribution to turnover.
Nestle came second in turnover with two parcels amounting to 193,000 shares changing hands at 350 rupees a share.
Vidulanka, with almost 2.3 million shares traded, was on top in terms of volume.
The share ended down 75 cents at 23.
25 rupees.
Dialog Telekom ended down 25 cents at 13.75 rupees and Sri Lanka Telecom down one rupee at 43.
50 rupees with 40,600 shares traded.
Distilleries was down 2.75 rupees to 95.25 rupees with 461,700 shares traded while National Development Bank fell four rupees to 145 rupees.