Preliminary Work and Taxpayer Data · Preliminary work to prepare tax returns
Filing requirements and due date
tax year · reviewed 2026-08-19 · I. Ohu
The rule
Who must file. A return is required from every individual whose gross income for the taxable year equals or exceeds the exemption amount (IRC § 6012(a)(1)(A)) — and the statute then carves out the individuals who need not file, by reference to the sum of the exemption amount and the basic standard deduction applicable to them. The carve-outs are stated separately for an individual who is unmarried and neither a surviving spouse nor a head of household, for a head of household, for a surviving spouse, and for a married couple entitled to file jointly whose combined gross income is below twice the exemption amount plus the joint standard deduction — the last of these applying only where the spouses had the same household as their home at the close of the year, and not where the spouse files a separate return.
That reads oddly until one fact is supplied: the exemption amount is zero — and permanently so for taxable years beginning after 2017, following Pub. L. 119-21 § 70103(a)TY2026. With the exemption at zero, the statutory test collapses to the practical one the IRS publishes — file where gross income reaches the applicable basic standard deduction.
When. IRC § 6072(a) requires a return made on a calendar year basis to be filed on or before the 15th day of April following the close of the calendar yearTY2026, and a return made on a fiscal year basis on or before the 15th day of the fourth month following the close of the fiscal yearTY2026. Individuals are almost always calendar-year taxpayers, so April is the answer for them; the fourth-month rule is what governs an estate or trust filing Form 1041 on a fiscal year, and that is where the rule is usually tested.
When the date falls on a weekend or holiday. IRC § 7503 makes an act timely if performed on the next succeeding day that is not a Saturday, Sunday or legal holiday. Two details in that section are easy to miss: the last day is determined including any authorised extension of time, and “legal holiday” means a legal holiday in the District of Columbia — which is why Emancipation Day moves the national filing deadline.
Current figures
| Filing status | 2026 basic standard deduction |
|---|---|
| Married filing jointly and surviving spouses | $32,200 for married individuals filing joint returns and surviving spousesTY2026 |
| Head of household | $24,150 for heads of householdTY2026 |
| Single | $16,100 for unmarried individuals other than surviving spouses and heads of householdTY2026 |
| Married filing separately | $16,100 for married individuals filing separate returnsTY2026 |
| An individual who may be claimed as a dependent | the greater of $1,350, or the sum of $450 and the individual's earned incomeTY2026 |
| Additional amount for the aged or the blind | an additional $1,650, increased to $2,050 where the individual is also unmarried and not a surviving spouseTY2026 |
| Other item | 2026 |
|---|---|
| Personal exemption amount | zero — and permanently so for taxable years beginning after 2017, following Pub. L. 119-21 § 70103(a)TY2026 |
| Deduction for seniors | $6,000 for each qualified individual who has attained age 65 before the close of the taxable year, for taxable years beginning before 1 January 2029TY2026 |
| Senior deduction phase-out | reduced by 6 percent of modified adjusted gross income above $75,000, or $150,000 on a joint returnTY2026 |
| Automatic extension to file | an automatic 6-month extension of time to file, on a complete application made on Form 4868 by the date prescribed for filingTY2026 |
| Extension for a taxpayer abroad | to and including the fifteenth day of the sixth month following the close of the taxable year, for a United States citizen or resident whose tax home and abode are outside the United States and Puerto Rico, or who is in military or naval service on duty outside themTY2026 |
How it works in practice
A gross income test, not a taxable income test. The § 6012 thresholds are measured against gross income, before deductions. A taxpayer whose deductions would eliminate any liability may still be required to file, and the question at intake is what came in, not what will be owed.
Self-employment changes the analysis entirely. The standard-deduction thresholds govern the income tax return requirement. A taxpayer with net earnings from self-employment at or above the statutory floor must file to report self-employment tax regardless of how far below the standard deduction their gross income falls. The same is true of a taxpayer who owes household employment tax, an additional tax on a retirement plan distribution, or repayment of an advance premium tax credit.
Filing when not required is often the right advice. A taxpayer below the threshold who had income tax withheld, or who qualifies for a refundable credit, gets nothing without a return. This is the most common practical failure on this topic, and it is a conversation to have at intake rather than in April.
The extension extends time to file, never time to pay. Reg. § 1.6081-4 grants an automatic six-month extension on a complete application filed by the date prescribed for filing — Form 4868, or another manner the Commissioner prescribes. Interest runs from the original due date regardless, and the failure to pay addition accrues on any balance not paid by then. A client who hears “extension” and understands “more time to pay” will be surprised by the notice.
Some extensions require no application at all. Reg. § 1.6081-5(a)(5) and (6) grant an extension to the fifteenth day of the sixth month following the close of the taxable year, of the time both to file and to pay the tax shown on the return, to a United States citizen or resident whose tax home and abode are, in a real and substantial sense, outside the United States and Puerto Rico, and to one in military or naval service on duty outside them — including non-permanent or short-term duty. This is a rule about where the taxpayer is, not about what they request, and where it applies the automatic six-month extension under § 1.6081-4 runs concurrently rather than consecutively.
Estates and trusts are on the fourth-month rule. An estate may adopt a fiscal year, and where it does, Form 1041 is due the fifteenth day of the fourth month after the close of that year. A calendar-year estate or trust is therefore on 15 April like an individual; a fiscal-year estate is not, and the arithmetic runs from the month the year closes.
Below the threshold, and owed a refund
Marisol Öztürk-Whitfield worked part of the year, earned about 11,400 dollars, and had roughly 640 dollars of income tax withheld. She is single, not a dependent, and assumes she need not file.
She is right that she is not required to file — her gross income is below the single standard deduction. She is wrong that filing is pointless. Without a return the withheld tax is simply kept, and if she is eligible for a refundable credit, that too goes unclaimed. The claim for refund is itself subject to a limitations period, so “I’ll get round to it” has an end date. The advice is short: no obligation, but file anyway, and file this year.
The self-employed client with almost no income
Desmond Achebe-Lindqvist earned about 4,900 dollars from freelance work and nothing else. His gross income is far below the single standard deduction and he concludes there is nothing to file.
The income tax threshold is not the only one that applies. Net earnings from self-employment at or above the statutory floor create a filing obligation to report and pay self-employment tax, whatever the income tax position. Filing also creates the earnings record that supports his future social security benefit, which is the argument that usually persuades a client who is unmoved by the obligation itself.
The estate with a fiscal year
An executor elects a fiscal year for a decedent’s estate ending on 30 June. The Form 1041 is diarised for the following 15 April by an assistant who knows that date as “the deadline.”
It is due on 15 October — the fifteenth day of the fourth month following the close of the fiscal year. April is the calendar-year answer, and an estate that has adopted a fiscal year is not on the calendar-year rule. The elective fiscal year is one of the genuine planning tools available to an estate, and the price of using it is that every subsequent date has to be recomputed rather than recalled.
How this has changed
Two changes govern the 2026 return and both come from Public Law 119-21, enacted 4 July 2025.
The zero personal exemption is now permanent. Section 151(d)(5) previously reduced the exemption amount to zero for taxable years 2018 through 2025 only, and it was scheduled to return for 2026. Section 70103(a) of the Act substituted “beginning after 2017” for “2018 through 2025” in the heading and struck the words “and before January 1, 2026” from the operative text. The practical consequence is that the § 6012 filing thresholds continue to be governed by the standard deduction alone rather than reverting to an exemption-plus-deduction computation, and material predicting a 2026 reversion is wrong.
A new deduction for seniors runs through 2028. Section 151(d)(5)(C) now allows a deduction of $6,000 for each qualified individual who has attained age 65 before the close of the taxable year, for taxable years beginning before 1 January 2029TY2026 for each qualified individual — the taxpayer if aged 65 before the close of the year, and on a joint return the spouse if likewise. It is reduced by 6 percent of modified adjusted gross income above $75,000, or $150,000 on a joint returnTY2026, using adjusted gross income increased by amounts excluded under the foreign earned income and possessions provisions. Two conditions attach: the qualified individual’s social security number must appear on the return, and a married taxpayer may claim it only on a joint return. It is separate from, and additional to, the existing extra standard deduction for the aged in § 63(f).
The rest of this topic is long-settled. Section 6072(a) has fixed the April and fourth-month dates since 1954, § 7503’s weekend and holiday rule with it, and the automatic six-month extension replaced the older two-step four-plus-two arrangement in 2005.
Exam focus
Know that the filing requirement is measured against gross income and that with the exemption amount at zero the working threshold is the basic standard deduction for the filing status. Know the calendar-year date and the fifteenth-day-of-the-fourth-month rule, and be ready for the fiscal-year version applied to an estate on Form 1041. Know that Form 4868 gives six months to file and nothing to pay, and that a taxpayer whose tax home and abode are abroad gets two months automatically without applying. Expect the additional standard deduction for age or blindness, and the separate dependent’s standard deduction formula, to appear as computations.
Check yourself
1. An individual dies on 1 May. The estate adopts a fiscal year ending 30 June. When is Form 1041 due, absent an extension?
A. 15 April B. 15 July C. 15 August D. 15 October
Answer: D. A fiscal-year return is due the fifteenth day of the fourth month following the close of the fiscal year; April is the calendar-year date.
2. The filing requirement under IRC § 6012 is measured against what?
A. Taxable income B. Adjusted gross income C. Gross income D. Net income after credits
Answer: C. A taxpayer whose deductions eliminate the liability may still be required to file.
3. What does a timely filed Form 4868 obtain?
A. Six months more to file and to pay B. An automatic six-month extension of time to file only C. Four months to file, extendable by a further two D. A waiver of interest on the unpaid balance
Answer: B. Interest runs from the original due date and the failure-to-pay addition continues to accrue.
4. A United States citizen whose tax home and abode are outside the United States has what extension without applying?
A. None; an application is always required B. To the fifteenth day of the sixth month following the close of the taxable year, for filing and for paying the tax shown on the return C. Six months, running after the ordinary extension expires D. To 15 April of the second following year
Answer: B — and the ordinary six-month extension runs concurrently with it, not after it.
5. A filing deadline falls on a day that is a legal holiday in the taxpayer’s state but not in the District of Columbia. What is the effect?
A. The deadline moves to the next business day B. The deadline is unchanged C. The deadline moves only for taxpayers resident in that state D. The taxpayer must file early
Answer: B. IRC § 7503 defines “legal holiday” as a legal holiday in the District of Columbia.
Change log
- Initial draft against Rev. Proc. 2025-32 and IRC § 151(d)(5) as amended by Pub. L. 119-21. Records that the zero personal exemption is now permanent and that a new senior deduction applies through 2028.
Related topics
- Taxpayer filing status (e.g., single, head of household) 1.1.1.e
- Use of prior years' returns for comparison, accuracy, and carryovers for current year's return 1.1.1.a
- Residency status and/or citizenship (e.g., citizen, visas, green cards, resident alien or non-resident alien, ITIN) 1.1.1.c
- Minor children's unearned income (Kiddie tax) 1.1.1.p
- ACA requirements (e.g., health insurance coverage, total household income, advanced premium tax credit, household size) 1.1.1.q
- Foreign account and asset reporting (e.g., FBAR, Form 8938) 1.1.1.o
- Special filing requirements (e.g. foreign income, presidentially declared disaster areas, Form 1040-NR, injured spouse) 1.1.1.n
- Sources of applicable exclusions and adjustments to gross income (e.g., foreign earned income exclusion, retirement plans, HSAs, alimony paid, health insurance, self-employment tax) 1.1.1.g
- Sources of tax payments and refundable credits (e.g., withholding, estimated payments, earned income tax credit) 1.1.1.k
- Additional required returns filed and taxes paid (e.g., employment, gifts, international information returns, and other information returns) 1.1.1.m
- Underpayment penalties and interest 1.4.1.c