Fairmount Line ridership jumped by nearly 35 percent during last month’s Red Line diversion on the Ashmont branch and Mattapan trolley, according to the MBTA and Keolis, the company that runs the commuter rail.

Together with other increases elsewhere in the system, the ridership on commuter rail “reached a new post-pandemic peak in October,” according to a statement from the T.

“Seeing ridership on Commuter Rail return and grow consistently to reach this milestone demonstrates that safe, reliable, and more frequent service can bring riders back to mass transportation,” said MBTA General Manager and CEO Phillip Eng. “

Abdellah Chajai, CEO of Keolis Commuter Services, added: “These latest ridership trends are proof that the all-day service, and more flexible fare products are meeting our passenger’s needs.”

The Fairmount Line was free for riders within the city during the 16-day pause in train and trolley service while workers replaced tracks and made station improvements. The T is planning other temporary pauses elsewhere in the system to make essential repairs over the next two years.