Filing the Final Tax Return After Death in Montana

Most Personal Representatives in Montana know they need to file a final income tax return for the person who died. What catches many of them off guard is discovering that this is only the beginning — the estate itself may become a separate taxable entity, generating its own income and requiring its own tax filings throughout the entire administration period.

Getting these filings right matters, both because errors carry penalties and because the final tax returns must be completed before the estate can be distributed and closed.

The Final Individual Income Tax Return

The first filing obligation is the decedent's final personal income tax return, covering the period from January 1 of the year of death through the date of death. This is not an estate return — it is the individual's last return, covering income earned while they were alive.

Federal: File IRS Form 1040, marking it as the final return for the decedent. The due date follows the normal April 15 deadline (or the next business day if that falls on a weekend or holiday) for the year of death.

Montana: File Montana Form 2 (the individual income tax return), also marked as a final return. Montana does not have a separate "final return" form — you use the same individual return and write "DECEASED" across the top, along with the date of death.

The Personal Representative signs the return in place of the decedent. If there is a surviving spouse and the couple filed jointly in prior years, a joint return can still be filed for the year of death — the surviving spouse and Personal Representative both sign.

Montana does not have a state estate tax or inheritance tax. A major relief for most families: if the estate is not large enough to trigger federal estate tax (the federal exemption is several million dollars), there is no Montana death tax to worry about. The filings discussed here are income taxes, not estate taxes on the transfer of wealth.

When the Estate Becomes a Taxpayer

Once a person dies, the estate itself becomes a separate legal entity for tax purposes. From the date of death forward, any income generated by the estate's assets is taxable income of the estate — not of the deceased person, and not (yet) of the beneficiaries.

Common types of estate income during administration include:

• Interest earned on bank accounts that remain open
• Dividends from investment accounts
• Rental income from real property that has not yet been transferred
• Business income if the decedent owned a business still operating during probate

If the estate earns any income during the administration period, the Personal Representative must file:

Federal: IRS Form 1041 (U.S. Income Tax Return for Estates and Trusts)

Montana: Montana Form FID-3 (Income Tax Return for Estates and Trusts)

Montana requires a copy of the federal Form 1041 to be attached to the state Form FID-3 filing. The state return is not a standalone form — it piggybacks on the federal computation and adjusts for Montana-specific differences.

Form FID-3 and the Schedule K-1 Obligation

When the estate distributes income to beneficiaries during the administration period, that income passes through to the beneficiaries and is taxed at their individual rates rather than at the estate level. To document these distributions, the Personal Representative must issue:

Montana Form FID-3 Schedule K-1 to each beneficiary who received a distribution of estate income.

The K-1 details each beneficiary's share of the estate's income, gains, losses, deductions, and credits for the tax year. Beneficiaries need this document to complete their own personal income tax returns. Failure to issue accurate K-1s creates compliance problems for both the estate and the beneficiaries.

The due date for Form FID-3 and the accompanying Schedule K-1s generally follows the federal 1041 deadline: the 15th day of the fourth month after the close of the estate's tax year.

Choosing the Estate's Tax Year

The estate is a separate taxpayer with its own employer identification number (EIN), which the Personal Representative obtains from the IRS using Form SS-4. The estate can choose any fiscal year end — it does not have to follow the calendar year. Choosing a fiscal year strategically can allow income to be deferred into a later tax period or aligned with beneficiary distributions in a tax-efficient way.

This is one area where the involvement of a CPA is genuinely useful. For a simple estate with minimal ongoing income (a bank account earning modest interest for a few months), the tax obligation is straightforward. For an estate with rental property, a business, or significant investment income during a multi-year administration period, professional tax preparation is the right call.

The Estate Tax Return: Federal Only, and Only for Large Estates

Montana has no state estate tax. If a federal estate tax obligation exists, the Personal Representative files IRS Form 706 (U.S. Estate and Generation-Skipping Transfer Tax Return). The federal filing threshold is several million dollars per estate — the exact amount adjusts periodically — and the vast majority of Montana estates are well below this threshold.

If you are uncertain whether a federal estate tax return is required, a CPA or tax attorney can run the calculation quickly based on the inventory of assets.

Practical Sequence for Most Montana Estates

For a typical Montana estate — one with modest assets, no business income, and administration completed within a year — the tax obligations break down simply:

1. File the final individual Montana Form 2 and federal Form 1040 by the normal April 15 deadline following the year of death
2. Obtain an EIN for the estate from the IRS if the estate will have any income, open accounts, or conduct formal probate
3. File Montana Form FID-3 and federal Form 1041 for each tax year the estate has income
4. Issue Schedule K-1s to any beneficiaries who received income distributions
5. Close the estate after confirming all tax obligations are satisfied and any outstanding tax refunds are received

Tax refunds owed to the decedent on the final return belong to the estate. The Personal Representative deposits these into the estate account and distributes them as part of the final distribution to beneficiaries.

The Montana Estate Settlement Guide walks through the full administrative sequence — including the tax filing obligations, the timeline for completing them, and the other financial steps that must be coordinated during the administration period. For most Montana estates, the tax obligations are manageable; the key is knowing what filings exist, in what order, and what happens when you miss a deadline.

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