Aims Although facial nerve palsy (FNP) is a well-recognised complication following head and neck cancer (HNC) surgery, its natural history remains poorly defined. We aimed to evaluate temporal trajectories in patient reported synkinesis and motor scores and characterise the benefit of surgical intervention. Methodology A retrospective cohort study was completed evaluating consecutive patients with FNP attending the Sydney Facial Nerve Clinic. Patient reported outcome measures (PROMs) included the Facial Disability Index total (FDI), physical (FDI-P), social (FDI-S), and Synkinesis Assessment Questionnaire (SAQ). Broken stick linear regression was used to assess the temporal plateau of PROM scores in flaccid and synkinetic disease. Results A total of 477 patients (1,149 visits; mean age 40 years; 65.6% female) were included; 75.3% had synkinetic and 24.7% flaccid palsy. Recovery trajectories were dissociated. Synkinesis worsened by 3.05% per month before reaching a plateau at 11.0 months (p<0.001; n=189), consistent with the recognised natural history of aberrant recovery. In contrast, motor recovery continued substantially longer, with FDI-P improving until 31.5 months (p=0.007) and FDI total until 36 months (p=0.040). In flaccid FNP, FDI total plateaued at 14 months, FDI-P at 17.8 months, and FDI-S at 11.5 months. Surgery significantly improved next visit FDI (+8.4%, p<0.001), FDI-P (+5.6%, p<0.001) and FDI-S (+10.4%, p<0.001). Conclusion Synkinesis and motor recovery follow distinct timelines in FNP. Synkinesis appears to reach its natural plateau at around 1 year, whereas motor recovery may continue for up to 3 years. Delayed referral does not uniformly worsen outcomes, with reconstructive surgical options shown to significantly improve patient quality of life in flaccid disease.