Abstract Background The range of products stocked and their promotions in food retail outlets in healthcare settings can affect food choices by staff, patients and visitors. The innovative Scottish Healthcare Retail Standard (HRS) is a national mandatory scheme requiring all hospital food retail outlets to change the balance of food products stocked and their promotion to comply with nutritional criteria and promotional restrictions. The aim is to facilitate healthier food choices in healthcare settings. This study examined the implementation of HRS and the impact on foods stocked and promoted. Methods The study aimed to examine implementation process and changes to the retail environment in relation to food promotions and choice. A sample of hospital retail outlets (n = 17) including shops and trolley services were surveyed using a mixed methods design comprising: (a) structured observational audits of stock, layout and promotions (with a specific focus on chocolate and fruit product lines), and (b) face-to-face, semi-structured interviews with the shop manager or nominated members of staff (n = 32). Data were collected at Wave 1 (2016), at the beginning and during the early stages of HRS implementation; and Wave 2, 12 months later, after the HRS implementation deadline. Results All outlets, both commercial and not-for-profit, in the sample successfully implemented HRS. Implementation was reported to be more challenging by independent shop managers compared to chain store staff. Retail managers identified areas where more implementation guidance and support could have been provided. The number of chocolate product lines and promotions reduced substantially between Waves 1 and 2, but with no substantial increase in fruit product lines and promotions. Despite initial negative expectations of HRS’s impact, managers identified some opportunities in the scheme and positive changes in the supply chain. Conclusions Positive changes in food retail outlets occurred after hospital shops were required to implement HRS. By creating a consistent approach across hospital shops in Scotland, HRS changed the food retail environment for hospital staff, visitors and patients. HRS provides a regulatory template and implementation learning points for influencing retail environments in other jurisdictions and settings.