Unfortunately, you may be stuck. The Marketplace expects that you will notify them of any changes in your household.
Are they filing their own returns? If so, you can divide all the amounts on your 1095-A between the 3 returns. You can allocate however you choose, as long as all three percentages amount to 100%.
Please see this information on how to determine your household for the PTC. PTC household
How does the marketplace establish household size to determine eligibility for the premium tax credit?
A person’s household for premium tax credit eligibility includes all the individuals on their tax return — the tax filer, the tax filer’s spouse (if married filing jointly), and any dependents. Everyone is included in the household, even family members who are not applying for coverage and those who are not eligible for a premium tax credit. For example:
- Maria and Simon are married and have one child, Elaine, whom they claim as a tax dependent. They have a tax household of three people and earn $35,000 a year (which is 161 percent of the poverty line in 2020). Elaine is eligible for the Children’s Health Insurance Program (CHIP), making her ineligible for a premium tax credit, but she’s still included in Maria and Simon’s household for determining premium tax credit eligibility.
- Suppose that Maria and Simon also have an older daughter, Cora, who is 22 and living at home with her parents. Cora just graduated from college and is working full-time. She cannot be claimed as a tax dependent by her parents and files her own taxes. Even though Cora lives with her family, she is a household of one for premium tax credit purposes because she cannot be claimed by her parents.
Who can be in a household together?
The composition of the household for premium tax credit purposes follows Internal Revenue Service (IRS) rules for filing status and dependents. For more information on tax rules, see The Health Assister’s Guide to Tax Rules.
The actual premium tax credit for the year will differ from the advance credit amount estimated by the Marketplace if your family size or household income as estimated at the time of enrollment is different from the family size or household income you report on your return. The more your family size or household income differs from the Marketplace estimates used to compute your advance credit payments, the more significant the difference will be between your advance credit payments and your actual credit.
Notifying the Marketplace about changes in circumstances as soon as they occur will allow the Marketplace to update the information used to determine your expected amount of the premium tax credit and adjust your advance payment amount. This adjustment will decrease the likelihood of a significant difference between your advance credit payments and your actual premium tax credit. Changes in circumstances that can affect the amount of your actual premium tax credit include:
- Increases or decreases in your household income, including lump sum payments like a lump sum payment of Social Security benefits or taxable distributions from an individual retirement account or other retirement arrangement
- Marriage
- Divorce
- Birth or adoption of a child
- Other changes to your household composition
- Gaining or losing eligibility for government sponsored or employer sponsored health care coverage
- Moving to another address
