Voter turnout in Wednesday's local elections reached 56.8 percent, a 19-year high. Some 23.46 million of 41.29 million voters went to the polls, the National Election Commission said.
That was the second highest turnout after the first local elections in 1995 (68.4 percent).
Turnout was up 2.3 percentage points from the last local elections in 2010.
The NEC expected turnout to exceed 60 percent due to the effect of high turnout during the two-day early voting period last Friday and Saturday, which was 11.49 percent. But overall turnout did not come up to the expectations, prompting concerns of vote splitting.
"Early voting did boost the turnout, considering that campaigning was muted in the wake of the ferry disaster and there were no hot-button political issues," an NEC spokesman said. "We believe that early voting actually boosted turnout by about five percentage points."
South Jeolla Province had the biggest proportion of voters with 65.6 percent, and exceed 60 percent in Jeju (62.8 percent), Sejong (62.7 percent), and Gangwon Province (62.3 percent).
Turnout in North Chungcheong Province (58.8 percent), where the race was neck-and-neck, also exceeded the overall average.
In the Seoul metropolitan area, turnout in Seoul was 58.6 percent, 1.8 percentage points more than the national average, but less in Gyeonggi Province (53.3 percent) and Incheon (53.7 percent).
The metropolitan city with the lowest turnout was Daegu, President Park Geun-hye's hometown, with 52.3 percent.
In Danwon District in Ansan, Gyeonggi Province, where most of the ferry disaster victims came from, turnout was 47.8 percent, 5.5 percentage points lower than Gyeonggi's average of 53.3 percent.