Background Understanding how financial well-being changes through the life course of caregiving parents of children with developmental disabilities is critically important. Methods We analyse SIPP (U.S. Census Bureau) data to describe income poverty, asset poverty, income, net worth, and liquid assets of US parents ( N = 753) of children with developmental disabilities. Results Income and asset poverty was greatest for the youngest and oldest parents. Liquid assets were relatively flat across cohorts, while net worth declined sharply for elderly parents. Income was highest among parents aged 45-54. Conclusion These findings signal significant financial vulnerability among parents of children with developmental disabilities. Policy makers should consider targeted measures to improve the financial well-being of these parents, particularly the youngest and oldest.