BackgroundDemand generation aims to increase clients’ desire to use family planning. The aim of this work was to systematically summarize strategies, facilitators, and barriers to scaling up and sustaining demand generation in family planning.MethodsWe searched electronic bibliographic databases from inception to October 2022. We included quantitative, qualitative, and mixed methods reports on demand generation strategies in family planning, regardless of country, language, publication status, or methodological limitations. We assessed abstracts, titles and full-text papers according to the inclusion criteria, extracted data, and assessed methodological quality of included reports. We used the convergent integrated approach and a deductive thematic synthesis to summarize demand generation themes and subthemes. We used the health system building blocks to synthesize the factors affecting implementation (barriers and facilitators). We used GRADE-CERQual to assess our confidence in the findings.ResultsForty-six studies (published 1990–2022) were included: forty-one quantitative, one qualitative, and four mixed methods). Three were from one high-income country, and forty three from LMIC settings. Half of reports were judged to be of unclear risk of bias. There were unique yet interrelated strategies of scaling-up demand generation for family planning. Interpersonal communication strategies increase adoption and coverage of modern contraceptive methods, but the effect on sustainability is uncertain. Mass media exposure increases knowledge and positive attitudes and may increase the intention to use modern contraceptive methods. Demand-side financing approaches probably increase awareness of contraceptives and the use of modern contraceptive methods among poor clients. Multifaceted Demand generation approaches probably improve adoption, coverage and sustainability of modern methods use. Factors that influence the success of implementing these strategies include users knowledge about family planning methods, the availability of modern methods, and the accessibility to services.ConclusionsDemand generation strategies may function independently or supplement each other. The myriad of techniques of the different demand generation strategies, the complexities of family planning services, and human interactions defy simplistic conclusions on how a specific strategy or a bundle of strategies may succeed in increasing and sustaining family planning utilization.Trial RegistrationSystematic review registration: Center for Open Science, osf.io/286j5