The Eliminating the Marriage Penalty in SSI Act would change how Supplemental Security Income, a federal assistance program for low-income individuals, treats married adults with intellectual or developmental disabilities. Currently, when someone receiving SSI gets married, their spouse's income and resources are counted against them, which can reduce or eliminate their benefits. This bill would stop that practice for adults with intellectual or developmental disabilities, allowing them to keep their full SSI benefits regardless of whether they marry or their spouse's financial situation. The change would apply to adults age 18 and older who have been diagnosed with an intellectual or developmental disability and meet the program's income and resource limits. The new rules would take effect for benefits beginning more than 180 days after the bill becomes law, if enacted.