In May transshipment container volumes rose 9.8 percent to 266,668 reversing a downward trend in earlier months, though total volumes in the first five months were still down 5.1 percent to 1.237 million TEUs.
Domestic container volumes fell 3.8 percent to 81,866, a trend that has continued for the third month running, data published by the Central Bank shows.
Sri Lanka's external trade has slowed in 2012 partly due to currency depreciation and higher interest rates.
Last year imports were driven to unsustainable levels with more than 200 billion rupees of central bank credit (printed money).
In May 2012, 342 ships had called at Sri Lanka's ports down from 361 a year earlier. Up to May 1715 ships had called, down from 1,794 a year earlier.
Total cargo discharged rose 5.5 percent to 16.6 million metric tonnes up to May 2012, though total cargo loaded fell 3.5 percent to 10.25 million tonnes.