Background The sickness certification and return to work (RTW) of people with chronic pain are important health and economic issues for employees, employers, taxpayers and the UK government. The 'fit note' and a national educational programme promoting RTW were introduced in 2010 to curb rising rates of sickness absence. Aims To investigate employers' and employees' experiences of managing RTW when someone has taken sick leave for chronic pain and to explore the perceived efficacy of the fit note. Methods A qualitative study, comprising semi-structured interviews with employers who had managed sick leave cases and employees who had experienced sick leave for chronic pain. Interviews were recorded, transcribed and the data analysed using constructivist grounded theory principles. Results Five themes were elicited. Firstly, frequent enquiry after health status was seen as intrusive by some employees but part of good practice by employers and acknowledging this difference was useful. Secondly, being able to trust employees due to their performance track record was helpful for employers when dealing with complex chronic pain conditions. Thirdly, feeling valued increased employees' motivation to RTW. Fourthly, guidelines about maintaining contact with absent employees were useful if used flexibly. Finally, both parties valued the fit note for its positive language, interrogative format and biomedical authority. Conclusions The fit note was perceived to be helpful if used in combination with other strategies for managing sick leave and RTW for people with chronic pain. These strategies may be applicable to other fluctuating, long-term conditions with medically unexplained elements.