Reductions in scope of benefits and stricter premium and co-payment policies in the Oregon Health Plan (OHP) led to a large drop in OHP enrollment. Outpatient psychiatric benefits were eliminated for approximately 25% of enrollees. One measure of access to care is ED use. We used administrative data from our ED from August 1, 2001, through June 30, 2004, comparing ED use before vs after the March 1, 2003, cutbacks. Before the cutbacks, 38% of ED visits were by OHP beneficiaries, falling to 32% afterward. Visits by the uninsured rose from 18% before to 22% afterward. The proportion of visits for psychiatric conditions covered by OHP fell from 41% [corrected] to 31% [corrected], although the proportion by uninsured patients rose from 16% to 23%. These findings suggest a worrisome reduction in access to medical care for uninsured Oregonians and unstable access for OHP enrollees, especially for behavioral health conditions.