The COVID–19 pandemic has challenged the capacity of healthcare systems around the world and can potentially compromise healthcare utilization and health outcomes among non-COVID–19 patients. Using monthly panel data of nationally representative middle-aged and older Singaporeans, we examined the associations of the pandemic with healthcare utilization, out-of-pocket medical costs, and perceived health. At its peak, doctor visits decreased by 30% and out-of-pocket medical spending decreased by 23%, mostly driven by reductions in inpatient and outpatient care. Although there were little changes in self-reported health and sleep quality, COVID–19 increased depressive symptoms by 4%. We argue that it is imperative to monitor COVID–19's long-term health effects among non-COVID–19 patients since our findings indicated delayed healthcare and worsened mental health during the outbreak.