ACA/FAMILY MEDICAID Filing Unit Determination
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Rules for determining ACA filing units for Montana Medicaid applicants based on IRS tax status, dependents, household composition, and age; applies to Medicaid eligibility staff and applicants processed under Montana DPHHS procedures.
No material clinical or coverage changes in this revision.
Filing Unit Determination Steps
Filing unit determination criteria
Determine the ACA filing unit by following Steps 1–3 below:
ALL of the following
- If not planning to file: If the individual does NOT plan to file current year taxes, proceed to Step 2.
If planning to file
- If no, the filing unit is based on the taxpayer's household, including spouse (if living together) and everyone they plan to claim as a dependent.
- If yes, proceed to Step 2.
ALL of the following
- If no: If the individual does NOT expect to be claimed as a dependent, continue to Step 3.
If yes — check exemptions
- Exemption i: They expect to be claimed by someone other than their biological, adoptive, or step-parent. If yes, continue to Step 3; if no, evaluate exemption ii.
- Exemption ii: They are a child under age 19 and either (1) living with both parents but the parents will not file jointly, OR (2) expect their non-custodial parent to claim them. If yes to either condition, continue to Step 3; if no to both, base the filing unit on the household of the taxpayer claiming them (include taxpayer's spouse if married).
ALL of the following
- The filing unit consists of the individual and, if living in the same house:
- a) Their spouse.
- b) Their natural, adoptive, and stepchildren under age 19.
- c) For individuals under age 19: include their natural, adoptive, and step parents, and siblings under age 19.
- d) For individuals over age 19: include the taxpayer(s) claiming them as a dependent only if the taxpayer is a natural, adoptive, or step-parent; also include the dependent's spouse if they live together.
Regulatory Reference / Codes
| 42 CFR 435.603(f) | Regulatory reference cited for filing unit determination |
Requirements for Eligibility Staff
Determine and create ACA filing unit using the 3-step IRS-based process
ACA filing units must be created for each applicant by following the stepwise determination process in this policy. Staff must determine the filing unit using the three-step question flow: (1) whether the individual plans to file current-year taxes; (2) whether the individual expects to be claimed as a tax dependent and, if so, whether any dependent exemptions apply; and (3) for individuals who do not file and are not claimed (or meet dependent exemptions), construct the filing unit based on household relationships (individual, spouse if cohabiting, natural/adoptive/stepchildren under age 19, and parents/siblings under 19 for minors).
- Create a filing unit for every applicant using the stepwise questions in the policy.
- Step 1: Ask if the individual plans to file current-year taxes; if yes, determine if they expect to be claimed as a dependent and follow Step 2 as needed.
- Step 2: If expected to be claimed, apply dependent exemptions (including special rules for those under age 19 or claimed by non-parent caregivers) to decide whether to base the filing unit on the claimant's household.
- Step 3: If the individual does not plan to file and is not expected to be claimed (or meets Step 2 exemptions), construct the filing unit to include the individual, their spouse if living together, natural/adoptive/stepchildren under 19, and for under-19 individuals include parents and siblings under 19; for over-19 dependents include the individual and the taxpayer(s) claiming them when the claimant is a natural/adoptive/step-parent and include the dependent's spouse if cohabiting.
Key Terms
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