The Pharmacy Integration Fund commissioned 95 cross‐sector pre‐registration trainee pharmacist placements across England, which incorporated trainees spending 3–6 months in general practice (GP), whilst employed in hospital or community pharmacy. Delivery models varied (blocks or split weeks/days); trainees had pharmacist tutors at the employing/base (hospital/community pharmacy) organisation and in GP. This study aimed to evaluate implementation of cross‐sector pre‐registration placements, and to identify barriers and enablers of a “successful” placement that achieved its intended outcomes. A qualitative study was undertaken, using semi‐structured interviews with triads/dyads of trainee and pharmacist tutors at base and/or GP site. Interviews explored trainees’ and tutors’ GP placement experiences, and the contribution of GP placements to achieving intended learning outcomes. Data were thematically analysed. Thirty‐four interviews (14 trainees, 11 base tutors, 9 GP tutors) were completed in 11 study sites (5 GP/hospital; 6 GP/community pharmacy). GP placements were perceived as valuable and producing well‐rounded pre‐registration trainees with a good understanding of two settings. Key benefits of GP placements were trainees’ ability to work within multidisciplinary teams, and improved clinical and consultation skills. Contingency planning/flexibility was important when setting up cross‐sector placements. GP tutor supervision which supported a gradual transition from shadowing to more independent clinical practice with feedback was perceived as valuable. Good collaboration between tutors at the base and GP site ensured joined‐up learning across settings. All participants considered 13 weeks in GP an appropriate minimum duration; community trainees preferred longer duration (26 weeks) for more opportunities for clinical and consultation skills learning. Base and GP tutors would welcome clarity on which pre‐registration competencies should be achieved in GP placements, which would also aid quality and consistency across providers. Findings from this study identified key attributes of a successful pre‐registration cross‐sector training experience. These findings can inform policy reforms including changes to initial education and training of pharmacists.