Race/ethnicity, education, and age are associated with engagement in ecological momentary assessment text messaging among substance-using MSM in San Francisco

•MSM of color had significantly lower adjusted odds of responding to EMA text messages 80% of the time or more•College-educated and young MSM had significantly lower adjusted hazard of week-long discontinuation of responding to EMA•Substance use variables were not correlated with engagement in text messages•EMA is a potentially useful research tool among active substance users•Future studies should further explore barriers to engagement in EMA texting for diverse populations of substance-using MSM