Objectives. Veterans are overrepresented within the homeless population compared with their non-veteran counterparts, particularly when controlling for poverty. The U.S. Department of Veterans Affairs (VA) aims to prevent new episodes of homelessness by targeting households at greatest risk; however, there are no instruments that systematically assess veterans' risk of homelessness. We developed and tested a brief screening instrument to identify imminent risk of homelessness among veterans accessing VA health care. Methods. The study team developed initial assessment items, conducted cognitive interviews with veterans experiencing homelessness, refined pilot items based on veterans' and experts' feedback and results of psychometric analyses, and assigned weights to items in the final instrument to indicate a measure of homelessness risk. Results. One-third of veterans who responded to the field instrument reported imminent risk of homelessness (i.e., housing instability in the previous 90 days or expected in the next 90 days). The reliability coefficient for the instrument was 0.85, indicating good internal consistency. Veterans who had a recent change in income, had unpaid housing expenses, were living temporarily with family and friends, needed help to get or keep housing, and had poor rental and credit histories were more likely to report a risk of homelessness than those who did not. Conclusion. This study provides the field with an instrument to identify individuals and households at risk of or experiencing homelessness, which is necessary to prevent and end homelessness. In addition, it supports VA's investment in homelessness prevention and rapid rehousing services for veterans who are experiencing or are at risk for homelessness.