Fighters of the Kurdish People's Protection Units (YPG) stormed IS's last remaining position, taking full control of Kobane, a powerful symbol of Kurdish resistance.
As they combed the streets looking for fugitive jihadists, the Kurdish fighters found more bodies, taking the civilian death toll to 206, the Syrian Observatory for Human Rights said.
Local journalist Rudi Mohammad Amin told AFP that more civilians were still unaccounted for.
The jihadists made their last stand in a boys' high school building.
"This military operation was carried out after ensuring that there were no civilians left in the school."
Amin said he believed all the IS fighters inside were killed.
The jihadists had entered Kobane at dawn on Thursday disguised in YPG uniforms and seized several buildings in the south and southwest of the town.
The YPG soon surrounded the buildings but it took two days to re-establish control.
Some of the civilians were felled in the streets by rocket or sniper fire, others were executed in their homes.
"The bodies were found littered in homes and in the streets, laying here and there," he said.
The IS operation was widely seen as vengeance for a series of defeats at the hands of Kurdish militia, particularly the jihadists' loss of Tal Abyad, another border town further east, on June 16.
"IS doesn't want to take over the town. They just came to kill the highest number of civilians in the ugliest ways possible," local journalist Mostafa Ali told AFP on Friday.
The Observatory chief said that IS had achieved its objective.
"You cannot call this last operation a real defeat for IS, because it did what it wanted to in Kobane," Abdel Rahman said.
