The voting will be held on September 21 during a nine-hour period, a spokesman for the Election Commissioner told AFP.
It will be the first-ever election for the Northern Provincial Council and Tamils are expected to win.
The area's capital Jaffna was the centre of a de facto state run by Tamil separatist rebels during the 37-year ethnic war.
Elections for two other councils elsewhere in the country will also be held on the same date.
President Mahinda Rajapakse's ruling coalition had promised to share limited power with Tamils through a local council after the military crushed the rebels in May 2009.
The councils in the north and elsewhere were established in line with an agreement with neighbouring India, which promised to rein in Tamil separatists on its soil provided Colombo's Sinhalese majority share political power with Tamils.
Although the government agreed to hold polls, it has moved to strip some powers from the councils, citing national security concerns should Tamils w