For the purpose of determining subsidy eligibility, the IRS and the health insurance exchanges use an ACA-specific version of modified adjusted gross income (MAGI). MAGI is based on household income, even if only one spouse is applying for a policy in the exchange. Although your total household income is obviously higher than your wife’s income alone, the poverty level for a household of two is also higher than the poverty level for a household of one. So while your income is counted when determining whether she’ll qualify for a subsidy, you’re also counted as part of the household when determining how the household’s income compares with the poverty level.