Background: The study aimed to assess the intention to accept a future COVID-19 vaccine in Nigeria and associated factors. Patients & Methods: A cross-sectional study was conducted using an online questionnaire between July 2020 and August 2020 that captured demographic data, risk perception; trust in government and public health authorities and willingness to accept a future COVID-19 vaccine. Data were analyzed using Statistical Package for Social Science and Chi-square and logistic regression at a 95% confidence interval calculated. Appropriate institutional ethical board approval and informed consent obtained from all participants were obtained. Results: 1,228 responses were received over the study period. The mean age of respondents was 32.8 years (SD 10.4), 12.7% (156/1,228) were health workers, and 66.9% (820/1,228) had tertiary level of education. Intention to accept a future COVID-19 vaccine was expressed by 50.2% (617/1,228). Older age, male gender, trust in government, trust in public health authorities, confidence in vaccine developers, willingness to pay for and travel for a vaccine, and vaccination during an outbreak were significantly associated with COVID-19 vaccine acceptance. Healthcare workers and respondents with pre-existing medical conditions were not significantly different from non-healthcare workers and persons without medical conditions respectively with regards to the willingness to be vaccinated. Conclusion: One in 2 persons would accept a COVID-19 vaccine when one becomes available in the country. The government should take pro-active steps to address the factors that may potentially impact on the benefits expected from the introduction of a COVID-19 vaccine in the country.