Objective: To assess variations in nutritional interventions during chemoradiotherapy (CRT) among the Dutch Head and Neck Oncology centres (HNOCs). Methods: An online questionnaire about nutritional interventions and dietetic practices was sent to 14 oncology dietitians of the HNOCs. Results: The response rate was 93%. The number of scheduled dietetic consultations varied from two to seven during CRT. Most centres (77%) reported using a gastrostomy for tube feeding in the majority of patients. Gastrostomies were placed prophylactically upon indication (39%) or in all patients (15%), reactive (15%), or both (31%). For calculating energy requirements, 54% of the dietitians used the Food and Agriculture Organization/World Health Organization and United Nations University (FAO/WHO/UNU) formula and 77% uses 1.2–1.5 g/kg body weight for calculating protein requirements. Almost half of the centres (46%) reported to remove the gastrostomy between 8 and 12 weeks after CR. Most centres (92%) reported to end dietary treatment within 6 months after CRT. Conclusion: This study shows substantial variation in dietetic practice, especially in the use of a gastrostomy for tube feeding, between the HNOCs. There is a need for concise dietetic guidelines.