question: Background: An understanding of willingness of people to disclose coronavirus disease 2019 (COVID-19) symptoms and take the COVID-19 test will help provide important insight for motivators towards the self-surveillance and testing strategies recommended by the World Health Organization to curtail and halt the transmission of COVID-19. Objectives: This study assessed willingness to disclose symptoms suggestive of COVID-19 and willingness to take COVID-19 test as well as their predictors. Methods: A cross-sectional online survey of 524 Nigerian adults, aged [≥] 18 years, residing in Nigeria and who had not taken the COVID-19 test was conducted. Information on willingness to disclose COVID-19 symptoms, take COVID-19 test and possible predictors were collected. Data were analysed using descriptive and inferential statistics evaluated at 5% significance level. Results: Mean age of respondents was 35.8 (S.D: 10.7) years and 57.0% were males. Majority (85.8% and 86.2% respectively) were willing to disclose COVID-19 symptoms and take COVID-19 test. Self-risk perception of contracting COVID-19 predicted both willingness to disclose COVID-19 symptoms (aOR=3.236; 95%CI=1.836-5.704) and take COVID-19 test (aOR=3.174; 95%CI=1.570-6.419). Willingness to disclose COVID-19 symptoms (aOR=13.060; 95%CI= 6.253-27.276), knowledge of someone who had taken the test (aOR= 4.106; 95%CI= 1.179-14.299) and thought that it was important for people to know their COVID-19 status (aOR=3.123; 95%CI= 1.516-6.434) also predicted willingness to take COVID-19 test. Conclusion: Nigerians are willing to disclose symptoms suggestive of COVID-19 and take the COVID-19 test. Investment in interventions developed based on the predicting factors will help speed up the finding and testing of suspected COVID-19 cases.