Published: June 23, 2026.
MAGI is modified adjusted gross income. The ACA Marketplace uses MAGI to determine APTC eligibility, CSR tiers, and whether a household falls into Medicaid instead of subsidized private coverage.
Key Takeaways
- MAGI is modified adjusted gross income. The ACA Marketplace uses MAGI to determine APTC eligibility, CSR tiers, and whether a household falls into Medicaid instead of subsidized private coverage.
- MAGI starts from adjusted gross income on the federal tax return and adds back certain exclusions such as non taxable Social Security and tax exempt interest. For most W-2 households, MAGI is close to AGI. Self employed clients require a closer look at business deductions.
- The Marketplace asks for projected annual MAGI at enrollment. Clients who understate income receive excess APTC and repay some of it on Form 8962. Clients who overstate income leave subsidy on the table until they report a change.
- Life events that change MAGI, such as marriage, divorce, job loss, or new self employment income, can open SEPs and should trigger subsidy recalculation during the plan year.
MAGI starts from adjusted gross income on the federal tax return and adds back certain exclusions such as non taxable Social Security and tax exempt interest. For most W-2 households, MAGI is close to AGI. Self employed clients require a closer look at business deductions.
The Marketplace asks for projected annual MAGI at enrollment. Clients who understate income receive excess APTC and repay some of it on Form 8962. Clients who overstate income leave subsidy on the table until they report a change.
Life events that change MAGI, such as marriage, divorce, job loss, or new self employment income, can open SEPs and should trigger subsidy recalculation during the plan year.
Related field notes
- ACA Marketplace enrollment for self-employed and 1099 clients: the income conversation
- Married or divorced: how it changes your ACA subsidy
- Do I qualify for an ACA subsidy? 2026 income limits and eligibility
Related glossary terms
FAQ
Common broker questions about this term.
Is MAGI the same as gross wages?
Not always. Gross wages are a starting point, but AGI and MAGI subtract certain deductions. Self employed clients often have MAGI well below gross revenue.
Whose income counts for a married couple?
Both spouses' income counts toward household MAGI when filing jointly. Marital status on December 31 of the tax year generally controls subsidy reconciliation.
Should brokers document MAGI assumptions?
Yes. A one line note on projected income and data source at enrollment reduces reconciliation disputes when 1095-A arrives in January.
