BackgroundCOVID-19 overwhelmed healthcare systems worldwide. Its impact on clinical staff is well documented, but little is known about the effects on ancillary staff (cleaners, porters and caterers).AimTo identify the evidence of the impact of COVID-19 on ancillary staff at National Health Service (NHS) hospitals in England.DesignSystematic review and narrative synthesis.Data sourcesDatabases (MEDLINE, CINAHL Ultimate, APA PsycINFO, APA PsycArticles and Academic Search Ultimate). Reference lists were searched. Four independent reviewers screened titles and abstracts against inclusion criteria. Data were extracted from included papers and studies were critically assessed using relevant critical appraisal tools.Results8/178 studies were included, of which 5 quantitative, 2 qualitative and 1 mixed methods. Ancillary staff had higher rates of past and present COVID-19 infection. Participants felt that the work of ancillary staff had been insufficiently recognised by managers and that they had little voice within the NHS. They also experienced inequity regarding available support and safe working practices due to largely digital modes of communication which they rarely, if ever, used. In an evaluation of a personal protective equipment support ‘helper’ programme, ancillary workers were more positive about it than nurses, allied health practitioners, and doctors.ConclusionFew studies included ancillary staff. As reported, ancillary staff at NHS hospitals had a higher prevalence of COVID-19 infection but felt marginalised and poorly supported. They valued training when offered. Additional research is needed to understand better the impact of COVID-19 on ancillary key workers, and how best to support them in future similar circumstances.