This paper investigates the affordability of private health expenditure among Irish households and the services contributing towards financial hardship. We use data from the Irish Household Budget Survey, a representative survey of household spending in Ireland, covering 2009-10 and 2015-16. Private health expenditure comprises out-of-pocket payments for health and social care services and private health insurance (PHI) premiums. The poverty threshold is 60% of median total equivalised consumption and households with consumption below this level were defined as poor. Households were classified as having unaffordable health expenditure if: 1) they were poor and reported any spending; 2) they were pushed below poverty threshold by health spending; or 3) their spending on health exceeded 40% of capacity to pay. Despite signs of economic recovery, the incidence of unaffordable private health spending increased over the years-from 15% in 2009-10 to 18.8% in 2015-16. People on low incomes were disproportionately affected. The largest component of unaffordable spending for poorer households is PHI and not user charges, which have actually fallen as a cause of hardship. Our findings indicate that reliance on private health expenditure as a funding mechanism undermines the fundamental goals of equity and appropriate access within the health care system. Copyright © 2019 Elsevier B.V. All rights reserved.