Narrative:

We pushed off of the gate and proceeded to runway xxl. We were cleared to takeoff up to 5000 ft. When the captain called for 'gear up' EICAS message 'lg lever disag' warning was presented. At this point we both looked to the gear pins and saw that the gear pins were missing from their respective holders. After cleaning up the aircraft and on a heading we relayed a message to dispatch via ACARS stating that we are returning to the gate due to gear pins still being installed. [The captain] made the decision that with the current weather conditions that it was safe to return back to runway xxr (the longest available runway) and also briefed overweight landing procedures. The touchdown was very gentle. When we returned to the gate [the captain] filled out a logbook entry and spoke to maintenance control. The maintenance gentleman did the appropriate inspections before signing off the necessary paperwork and we then left for ZZZ.go slow; take your time; always double check gear pins.

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Original NASA ASRS Text

Title: EMB175 flight crew reported the landing gear would not retract because the gear pins were still installed. The flight returned to the departure airport where they were removed and the flight continued on.

Narrative: We pushed off of the gate and proceeded to Runway XXL. We were cleared to takeoff up to 5000 ft. When the captain called for 'gear up' EICAS message 'LG LEVER DISAG' Warning was presented. At this point we both looked to the gear pins and saw that the gear pins were missing from their respective holders. After cleaning up the aircraft and on a heading we relayed a message to dispatch via ACARS stating that we are returning to the gate due to gear pins still being installed. [The Captain] made the decision that with the current weather conditions that it was safe to return back to Runway XXR (the longest available runway) and also briefed overweight landing procedures. The touchdown was very gentle. When we returned to the gate [the Captain] filled out a logbook entry and spoke to Maintenance Control. The maintenance gentleman did the appropriate inspections before signing off the necessary paperwork and we then left for ZZZ.Go slow; take your time; always double check gear pins.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.