This study aimed at investigating the change in social eating problems from diagnosis to 24 months after primary (chemo)radiotherapy and its associations with swallowing, oral function, and nutritional status, in addition to the clinical, personal, physical, psychological, social, and lifestyle dimensions. Adult patients from the NETherlands QUality of life and BIomedical Cohort (NET-QUBIC) treated with curative intent with primary (chemo)radiotherapy for newly-diagnosed HNC and who provided baseline social eating data were included. Social eating problems were measured at baseline and at 3-, 6-, 12-, and 24-month follow-up, with hypothesized associated variables at baseline and at 6 months. Associations were analyzed through linear mixed models. Included patients were 361 (male: 281 (77.8%), age: mean = 63.3, SD = 8.6). Social eating problems increased at the 3-month follow-up and decreased up to 24 months (F = 33.134, p < 0.001). The baseline-to-24 month change in social eating problems was associated with baseline swallowing-related quality of life (F = 9.906, p < 0.001) and symptoms (F = 4.173, p = 0.002), nutritional status (F = 4.692, p = 0.001), tumor site (F = 2.724, p = 0.001), age (F = 3.627, p = 0.006), and depressive symptoms (F = 5.914, p < 0.001). The 6–24-month change in social eating problems was associated with a 6-month nutritional status (F = 6.089, p = 0.002), age (F = 5.727, p = 0.004), muscle strength (F = 5.218, p = 0.006), and hearing problems (F = 5.155, p = 0.006). Results suggest monitoring social eating problems until 12-month follow-up and basing interventions on patients’ features.