ObjectiveCancer survival rates have improved over the past few decades, yet socioeconomic disparities persist. Social determinants of health (SDOH) have consistently been shown to correlate with health outcomes. The objective of this study was to characterise oncologists’ perceptions of the impact of SDOH on their patients, and their opinions on how these effects could be remediated.DesignCross-sectional survey of physicians.SettingWeb-based survey completed prior to live meetings held between February and April 2020.ParticipantsOncologists/haematologists from across the USA.ExposureClinical practice in a community-based or hospital-based setting.Main outcome and measurePhysician responses regarding how SDOH affected their patients, which factors represented the most significant barriers to optimal health outcomes and how the impact of SDOH could be mitigated through assistance programmes.ResultsOf the 165 physicians who completed the survey, 93% agreed that SDOH had a significant impact on their patients’ health outcomes. Financial security/lack of insurance and access to transportation were identified most often as the greatest barriers for their patients (83% and 58%, respectively). Eighty-one per cent of physicians indicated that they and their staff had limited time to spend assisting patients with social needs, and 76% reported that assistance programmes were not readily accessible. Government organisations, hospitals, non-profit organisations and commercial payers were selected by 50% or more of oncologists surveyed as who should be responsible for delivering assistance programmes to patients with social needs; 42% indicated that pharmaceutical manufacturers should also be responsible.ConclusionOur survey found that most oncologists were aware of the impact of SDOH on their patients but were constrained in their time to assist patients with social needs. The physicians in our study identified a need for more accessible assistance programmes and greater involvement from all stakeholders in addressing SDOH to improve health outcomes.