Background: Finite options exist to address free flap failure. There is a lack of consensus on the standard treatment for secondary reconstruction in such cases. Herein, the authors determined the survival rate of a second flap following a total loss of an initial free flap during head and neck reconstructions and evaluated whether there was a difference in the rate of secondary flap necrosis depending on the timing of reconstruction salvage. Methods: The authors retrospectively reviewed 1572 free flaps for head and neck reconstruction from 2010 to 2022. Patients who underwent secondary surgery with flaps after failure of a primary free flap were included. Patients were divided into three groups based on the time for secondary flap reconstruction from the time of primary reconstruction (group A, 0 to 5 days; group B, 6 to 30 days; and group C, >30 days). Results: The authors identified 64 cases of complete flap loss after primary reconstruction requiring secondary reconstruction. Pedicled flaps were used in 34.4% of the cases, whereas a second free flap was used in 65.6% of the cases. Overall, the flap failure rate for secondary reconstructions was 6.7% in group A, 35.3% in group B, and 6.7% in group C (P = 0.022). For free tissue transfer, the success rate of a secondary reconstruction was 92.3% in group A, 28.57% in group B, and 93.3% in group C. Conclusions: The authors favor an early microsurgical reconstruction (≤5 days) following primary reconstruction in cases of free flap failure. If early reconstruction cannot be performed, a deferred reconstruction with free tissue transfer (>30 days) should be considered. © 2024 Elsevier B.V., All rights reserved.