That was a sharp drop from 62 percent registered in the first stage of the last parliamentary poll, held in 2011 months after the ouster of longtime president Hosni Mubarak.
Observers say the outcome of the election, which ends on December 2, is a foregone conclusion. The 596-member parliament is expected to firmly present President Abdel Fattah al-Sisi's iron-fisted policies in the absence of any opposition.
"The percentage of voters participation was 26.56 percent," Ayman Abbas, head of the Electoral Commission told reporters at a press conference.
All of the 103 constituencies from the first round will hold a run-off vote on October 27-28, Abbas said.
The second and final round of the election will be held on November 21, with any necessary runoff being held on December 2.