R0000-940-13: Tax period end date not valid for tax year 2026

What this rejection means

Each IRS form year accepts only certain tax year end dates. Your return or extension was sent as a tax year 2026 filing, but its end date is not one the rule allows.

IRS business rule R0000-940-13: For a return filed for tax year 2026, the tax period ending date 'TaxPeriodEndDt' in the Return Header must be [ one of the following values ("20261231", "20270131", "20270228", "20270331", "20270430", "20270531", "20270630", "20270731", "20270831", "20270930", "20271031", "20271130") OR (1-3 days after the beginning of the month) OR (1-6 days before the end of the month) ] unless one of the following is true: 1. checkbox "Final Return" or "Final return/terminated" or "Termination" is checked. 2. checkbox "Initial Return" is checked. 3. Return is a short year return (i.e., difference between "Tax Period Beginning Date" and "Tax Period Ending Date" is less than 12 months.

In plain English: a full 12-month tax year 2026 return must end on the last day of a month from December 31, 2026 through November 30, 2027. Dates a few days either side of a month boundary are also allowed. First-year returns, final returns and periods shorter than 12 months are exempt.

Why it happens

• The wrong form year was used. The Form 990-EZ instructions say a year's form covers the calendar year and fiscal years that began in that year. A fiscal year from July 1, 2025 to June 30, 2026 belongs on the 2025 form. Sending it as a 2026 return triggers this rule.
• A typo in the end date, such as the wrong year, or a day that is not near the end of a month.
• An unusual first or last year without the box checked. If this is your first return or your final return, the Initial return or Final return box must be checked for the exception to apply.
• A changed accounting period. If the organization changed its year end, the return for the change is a short period. That period must really be shorter than 12 months.

How to fix it

1. Confirm your accounting period. Look at the start and end dates of the year you are reporting.
2. Check the form year. If your year began in 2025, file the 2025 version. If it began in 2026, file the 2026 version. Your e-file provider chooses which year's version is sent, so tell them if it looks wrong.
3. Correct the end date if it was mistyped, and send the return again.
4. Check the Initial return or Final return box only if it truly applies.
5. If you changed your year end, the IRS says to file a return for the resulting short period, with "Change in Accounting Period" noted. If the organization already changed its accounting period within the last 10 calendar years, it must use Form 1128.

Picking the form version and filling in the tax year fields is part of your e-file software's job. If your dates are right and the rejection repeats, contact your e-file provider.

When to contact the IRS

You do not usually need to. This rule checks the date and the form version, not the IRS record. A separate rule, TEGE-911, compares your end date with the year end the IRS has on file. If you get that one too, the IRS record may need to be reviewed.

Related codes

• TEGE-911: the tax period end date must match the year end the IRS has on record.
• R0000-160: the tax period cannot be longer than 12 months.
• R0000-201: the end date cannot be earlier than the begin date.
• R0000-931-02: the return cannot be received before the tax period ends, unless it is a final return.