Background Recruitment of individuals with rare diseases for studies of real-world patient-reported outcomes is limited by small base populations. Myeloproliferative neoplasms (MPNs) are a group of rare, chronic, hematologic malignancies. In this study, recruitment strategies and geographic representativeness from the Living with MPNs survey are reported. Methods The Living with MPNs online cross-sectional survey was conducted between April and November 2016. Individuals 18 to 70 years of age living in the United States and diagnosed with an MPN were eligible to participate. Recruitment approaches included direct contact via emails and postcards; posts on MPN-focused social media and patient advocacy websites; postcard mailings to doctors’ offices; and advertisements on medical websites, Google, and Facebook. Geographic representativeness was assessed based on the number of survey respondents living in each state or the District of Columbia and by the number of survey respondents per 10 million residents. Results A total of 904 respondents with MPNs completed the survey. The recruitment method yielding the greatest number of respondents was advertisements on MPN-focused social media (47.6% of respondents), followed by emails (35.1%) and postcards (13.9%) sent through MPN advocacy groups. Home state information was provided by 775 respondents from 46 states (range of respondents per state, 1–89). The number of respondents per 10 million residents in the 46 states with respondents ranged from 12.1 to 52.7. Conclusions Recruitment using social media and communications through patient groups and advocacy organizations are effective in obtaining geographically representative samples of individuals with MPNs in the United States. These approaches may also be effective in other rare diseases.