Form 1128, Explained: How to Change Your Business's Tax Year — Automatic vs. Ruling-Request Approval, the Business-Purpose Test, Short Tax Years, and the Filing Deadline for Asking

Your busiest season ends in February, but your tax year ends December 31 — right in the middle of the chaos. Every year-end close collides with peak workload: inventory sits at its highest exactly when you would rather count it at its lowest, your accountant wants clean books while you are still fulfilling holiday orders, and the return gets filed on numbers everyone was too busy to double-check. Moving your year-end to March or June would fix all of that. The catch is that you cannot simply start filing on a different year. Under Section 442 of the tax code, your new tax year counts only if the IRS approves the change — and Form 1128, Application to Adopt, Change, or Retain a Tax Year, is the single form that asks for that approval.

This guide walks through how that request actually works: the two approval tracks, the business-purpose test most filers have to satisfy, the short tax year the change creates, and the filing deadline that decides which track you are on.

Why you need permission at all​

A tax year is the 12-month period your return covers — usually either the calendar year ending December 31 or a fiscal year ending on the last day of some other month. When you filed your first return, you adopted a tax year by doing so, and the IRS treats that choice as binding. Section 442 says a new taxable year becomes your taxable year only with the Secretary's approval, and the regulation behind it requires you to show a business purpose for the change. The policy reason is straightforward: without approval, a business could hop between year-ends to defer income or bunch deductions, so the IRS wants to see that your reason is operational rather than tactical.

Form 1128 is the vehicle for three different requests: adopting a year, changing a year (the common case this guide covers), and retaining a year when an ownership change would otherwise force a new one. Everyone completes Part I with identifying information and the current and requested years. Then you take one of two paths: Part II for automatic approval, or Part III for a ruling request. Which path you qualify for changes the deadline, the fee, the waiting time, and where the form gets mailed — so figuring that out comes first.

Which tax years are even available to you​

Before reaching for the form, check what years your entity type is allowed to hold. The rules are not the same for everyone:

• C corporations have the most freedom. A C corporation generally uses whatever year it adopted on its first return and can change it through the automatic approval procedure, as long as it does not fall into one of the excluded categories.
• S corporations, partnerships, and personal service corporations are the restricted group. They generally must use a required tax year — for most small ones, that means the calendar year, or the year the majority owners use. They can escape the required year only through a natural business year, a Section 444 election, or a business-purpose ruling, each explained below.
• Sole proprietors and single-member LLCs report business income on Schedule C of the owner's individual return, so the business year must match the owner's individual year. If you file your 1040 on a calendar year, your Schedule C is on a calendar year too. Changing the business year means changing your individual year, which has its own automatic procedure for moves to the calendar year.

If none of the automatic procedures fits your situation, you are not out of options — you are on the ruling-request track, which approves any reasonable business purpose but costs a user fee and months of waiting.

The two tracks: automatic approval vs. ruling request​

Track 1: automatic approval (Form 1128, Part II)​

Automatic approval means what it says: meet every condition of the revenue procedure for your entity type and approval is granted by the procedure itself. No ruling letter arrives, no agent reviews your business reason, and no user fee is due. You are deemed to have established a business purpose simply by qualifying.

The procedures that matter for small businesses:

• Rev. Proc. 2006-45 — C corporations (other than S corporations and personal service corporations) changing their year. You complete Part II, Section A, and write "FILED UNDER REV. PROC. 2006-45" at the top of the form. Automatic approval is unavailable if the corporation changed its year within the preceding 48 months, among other scope exclusions.
• Rev. Proc. 2006-46 — partnerships, S corporations, electing S corporations, and personal service corporations adopting, retaining, or changing to a permitted year, including a natural business year that passes the 25-percent test. Part II, Section B, labeled "FILED UNDER REV. PROC. 2006-46."
• Rev. Proc. 2003-62 — individuals changing to the calendar year. Part II, Section C.
• Rev. Proc. 85-58 — certain taxpayers changing to a calendar year or to specific permitted years. Part II, Section D, with its own deadline.

File an automatic request with the service center where you file your income tax return — the instructions say to address it to Entity Control — and attach a copy of the Form 1128 to the federal return you file for the short period the change creates. The instructions warn explicitly against mailing an automatic request to either of the ruling-request addresses: doing so causes a significant processing delay.

Track 2: ruling request (Form 1128, Part III)​

If your change fits no automatic procedure, you file Form 1128 as a ruling request under Part III. The same form, a different journey: it goes to the IRS National Office with a user fee, an agent reviews your stated business purpose, and the answer takes months rather than being effective on filing. The fee schedule is updated every year in the first revenue procedure of the year, so check the current amount before filing — ruling-request fees run into the thousands of dollars, which is itself a reason to squeeze into automatic approval whenever you honestly can. The ruling track also carries a stricter deadline, covered below, and missing it means asking for late relief, which is itself a ruling request with its own fee.

The business-purpose test and the 25-percent natural business year​

Every change needs a business purpose — some genuine operational reason the requested year fits the business better. Automatic-approval filers are deemed to satisfy this by meeting the procedure's conditions. Everyone else must state and support the purpose in the application.

The most common purpose, and the only one with a mechanical test, is the natural business year: your business has a natural annual low point — a seasonal trough when inventory is smallest, receivables are collected, and the books are easiest to close — and your year should end there. A ski retailer whose shelves empty out by April, a tax practice that exhales in June, a landscaper idle in January: each has a natural year-end that is not December 31.

For partnerships, S corporations, and personal service corporations, Rev. Proc. 2006-46 makes this objective through the 25-percent gross receipts test. You supply monthly gross receipts for the most recent 47 months, and the test asks whether at least 25 percent of receipts in the 12-month period ending with your requested year-end fall in its final two months — measured across three consecutive 12-month periods. Pass it and you are deemed to have a natural business year, which unlocks automatic approval. Fail it and you can still argue a natural business year on the ruling track with facts and circumstances, but you lose the automatic path.

Other purposes the IRS recognizes include conforming to the tax year of a parent company or majority owner, matching the year your books and records are actually kept on, and regulatory or foreign-law requirements. What does not count is tax timing for its own sake: wanting to defer income into a later year, standing alone, is not a business purpose.

The Section 444 alternative: a fiscal year without proving business purpose​

Partnerships, S corporations, and personal service corporations have one more door that requires no business purpose at all: the Section 444 election. It lets you elect a fiscal year whose deferral period — the months between the new year-end and the required year-end — is no longer than three months. A calendar-year S corporation can elect a September 30, October 31, or November 30 year-end, but nothing earlier.

The price of skipping the business-purpose test is that the election neutralizes most of the deferral benefit. Electing partnerships and S corporations generally must make annual required payments under Section 7519, which approximate the tax the owners defer; personal service corporations must meet a minimum distribution requirement instead. You elect on Form 8716, and terminating the election later sends you back through Form 1128. Section 444 is worth pricing out when your only goal is moving year-end out of the December crush by a month or two — for a deeper move to a true natural year, the Form 1128 routes fit better.

The short tax year: what actually happens to your filing​

Changing your year always creates a short tax year — a stub period of fewer than 12 months bridging the old year and the new one. If your calendar-year business switches to a June 30 year-end, January 1 through June 30 becomes a short year, and July 1 starts the first full fiscal year. Several consequences surprise first-time filers:

• You file a separate return for the short period. It is a real return with its own deadline, computed under the normal rules for a tax year ending on the short period's last day. A C corporation's short-period return, for example, is due by the 15th day of the fourth month after the short period ends.
• Short-period income generally must be annualized. Under Section 443, you scale the short period's income up to a 12-month equivalent to compute the tax, then scale the tax back down — so a profitable six months does not get taxed at the lower rates its smaller absolute dollars would suggest.
• Deduction and credit limits may be prorated. Depreciation, the Section 179 expensing limit, and various other annual caps are reduced to reflect the short year, which can meaningfully change the return's bottom line.
• Your estimated tax calendar shifts. Quarterly estimates follow the new year, so mark the new due dates the day the change takes effect rather than discovering them when a penalty notice arrives.
• Payroll filings stay on the calendar year. Forms 941, W-2, and 940 follow the calendar year no matter what your income tax year is. Your income tax year and your employment tax year are independent systems — do not try to move them together.
• Your books must genuinely close on the new year-end. The IRS expects the year you report on to be the year your records are kept on. A fiscal year that exists only on the tax return, while the books still close every December, undermines the business purpose the approval rested on.

The filing deadline — and why the tracks differ​

Deadlines are where the two tracks diverge most sharply, and getting them confused is the costliest mistake in this process.

• Automatic approval (Rev. Proc. 2006-45, 2006-46, and the individual procedure): file Form 1128 by the due date, including extensions, of the return for the short period required to effect the change. The extension-inclusive deadline is generous on purpose — it lets you decide as late as the extended return date.
• Ruling requests: file by the due date, not including extensions, of the return for the first effective year — which, for a change, is the short period. And you may not file before the short period ends: the earliest permitted filing date is the day after it closes. An application submitted before the short period ends generally will not even be considered.
• Rev. Proc. 85-58 changes: file by the 15th day of the fifth calendar month after the end of the short period.

What if you miss the date? Applications filed within 90 days after the due date may still be treated as timely if you establish reasonable, good-faith conduct. Beyond 90 days, the application is presumed to jeopardize the government's interests and will be approved only in unusual and compelling circumstances. Either way, late relief requires an extension request under Regulation section 301.9100 — itself a ruling request with its own user fee. Calendar the deadline the day you decide to change years, and if you are anywhere near the line, file early rather than testing how reasonable your good faith looks to a reviewer.

A step-by-step checklist for the change​

1. Confirm your entity type has somewhere to go. C corporations pick from the automatic procedure; S corporations, partnerships, and personal service corporations check the required-year rules, the 25-percent test, and Section 444 before concluding they need a ruling.
2. Run the 25-percent test early if you are a pass-through. Pull 47 months of monthly gross receipts and see whether your preferred year-end passes mechanically. The answer decides your track.
3. Pick your track and its deadline. Automatic means extension-inclusive timing and the service center; ruling means no extensions, the National Office, a user fee, and no filing before the short period ends.
4. Model the short period before you commit. Annualized income, prorated depreciation and Section 179 limits, and the shifted estimate schedule can make one year-end materially more expensive than another.
5. Prepare to close the books on the new year-end for real. Adjust your month-end checklist, your inventory count schedule, and your close calendar so the fiscal year exists in your records, not just on the return.
6. File Form 1128, then file the short-period return with a copy attached (automatic track), and notify your state. Many states require their own approval or at least conformity with the federal change — a federal approval does not automatically move your state year.
7. Reset the recurring calendar. New estimate dates, new return due date, new extension date. Payroll forms stay put.

Closing the books cleanly at the cutoff​

The bookkeeping moral of this whole process is that the short period must be a genuine hard close: every prior-period item booked, every accrual recorded, and the new fiscal year opened from verified balances. In a plain-text ledger, that means starting the new year with explicit opening balances and a balance assertion that proves the cutoff. If your new July-to-June fiscal year begins with $12,400 in checking and the first sale of the new year brings in $2,500, the file opens like this:

2026-07-01 open Assets:Checking
2026-07-01 open Income:Sales
2026-07-01 open Equity:Opening-Balances
 
2026-07-01 * "Opening balances" "New July-June fiscal year"
  Assets:Checking   12,400.00 USD
  Equity:Opening-Balances
 
2026-07-05 * "First sale of the new fiscal year"
  Assets:Checking   2,500.00 USD
  Income:Sales     -2,500.00 USD
 
2026-07-06 balance Assets:Checking  14,900.00 USD

That trailing balance assertion is doing the real work: it fails loudly if any short-period straggler gets posted into the new year with a July date, exactly the error a mid-year cutoff invites. Run the same discipline in reverse at the short-period end — reconcile every account through June 30 before anything dated July enters the file — and the short-period return ties to the books without a reconciliation footnote. The documentation covers balance assertions and opening balances in more depth if either is new to you.

Your last useful step is the calendar entry: the day the change takes effect, write down the new estimate dates, the short-period return due date, and the first full-year return due date. Form 1128 gets you the year you want; the calendar keeps it.