Blog · 14 October 2026

Form 1040-X Amended Returns After El Deeb: Incomplete Amendments, Refund Deadlines and What US CPA Firms Should Tell Clients

By Keshav Bansal, CA

An amended return only helps once the IRS has processed it. In El Deeb v. Commissioner, T.C. Memo. 2026-101 (filed September 29, 2026; Judge Jones), a taxpayer mailed a Form 1040-X reporting wages she had left off her 2021 return. The IRS never processed it, and its Automated Underreporter program later issued a notice of deficiency for the same wages. The Tax Court sustained the unreported income and held it had no jurisdiction over a disputed $3,000 estimated tax payment. For US CPA firms, the case is a reminder to amend completely, on time and in a way you can track.

What happened in El Deeb

Per the opinion, Ms. El Deeb’s 2021 Form 1040 (dated March 6, 2022) reported $28,230 of wages, $1,381 of total tax and $11,786 of total payments, including refundable credits and $3,000 of “2021 estimated tax payments and amount applied from 2020 return.” On or about April 11, 2022, the IRS refunded $7,405 of her claimed $10,405 overpayment, because it had no record of the $3,000.

She then mailed a Form 1040-X dated May 26, 2022. It reported a $16,027 increase to AGI, $3,254 of total tax, $520 of additional withholding and a $3,380 computational decrease to her earned income tax credit (EITC). The IRS never processed it.

On January 2, 2024, the IRS’s automated underreporter program issued a notice of deficiency: a $5,518 deficiency and a $1,000 §6662(a) penalty. The adjustments were $16,026 of unreported Aerotek, Inc. wages, a $519 withholding credit, $800 of income reported by the Research Foundation for SUNY, and an EITC computational change. She petitioned on March 20, 2024. The next day, the IRS sent Letter 2626C, saying the amended return could not be processed because it did not include or address the $800. By then it had been unprocessed for about 22 months.

A second Form 1040-X (April 30, 2024, sent to IRS counsel) added the $800. The parties then stipulated $16,027 of unreported Aerotek wages, a $520 withholding credit, that the $800 was not taxable, a $6,000 child tax credit ($3,000 paid in advance) and a $2,830 refundable child and dependent care credit. The IRS conceded the penalty. The court sustained the wage adjustment and noted that, with more earned income, the EITC “will necessarily change.” Decision will be entered under Rule 155.

Why the court could not rule on the $3,000

Under IRC §6211(b)(1), a deficiency is figured “without regard to payments on account of estimated tax,” and the court said that also covers a prior-year overpayment credited to estimated tax. Citing Bregin v. Commissioner, 74 T.C. 1097 (1980), it held that an adjustment to a payment credit outside the deficiency computation is not a deficiency, so it lacked jurisdiction. (Ms. El Deeb had also conceded the $3,000.) A missing estimated payment or carryover has to be sorted out with the IRS outside the 90-day case. See our posts on notices of deficiency and the 90-day petition and the estimated tax penalty quick read.

Form 1040-X basics

• What it fixes: per the IRS “File an amended return” page, a change in filing status, income, deductions, credits, dependents or tax liability. No amendment is needed if the IRS says it corrected errors on the return.
• E-file: Form 1040-X can be e-filed with tax software; the IRS says to amend on paper for tax year 2021 or earlier. Up to 3 amended returns can be filed for the same year.
• Complete returns: the December 2025 Form 1040-X instructions require a paper 1040-X to include a completed, updated Form 1040. Column A shows amounts as filed or as previously adjusted by the IRS.
• Wrong form for some requests: use Form 843 for a refund of only penalties and interest, and Form 8379 for an injured spouse allocation. Overclaiming a refund can bring a 20% penalty on the disallowed amount.

Refund claim deadlines under §6511

Under §6511(a), a refund claim is due within 3 years from when the return was filed or 2 years from when the tax was paid, whichever is later. Per Topic 308, an early return is treated as filed on the due date, and withholding as paid on that date. Under §6511(b)(2), a claim within the 3-year window recovers only tax paid in the 3 years before it (plus any extension); otherwise the lookback is 2 years. Disasters, combat zones, bad debts, worthless securities, foreign tax credits and carrybacks can allow more time. Hypothetical (our arithmetic): a 2023 return filed early, with tax paid by withholding, is treated as filed April 15, 2024, so a refund claim is generally due by April 15, 2027.

Timing: amend before the IRS asks

The IRS CP2000 page tells taxpayers to wait for all income documents before filing and to report anything received later on an amended return. Under Treas. Reg. §1.6664-2(c)(2)–(3), additional tax shown on a qualified amended return, generally one filed before the IRS first contacts the taxpayer about an examination, counts as tax shown on the return for accuracy-related penalty purposes. The opinion does not say why the IRS conceded the penalty in El Deeb, so don’t treat that as a rule. If a CP2000 is correct and the client has other items to report, the IRS says to write “CP2000” at the top of the 1040-X and send it with the notice response. See our IRS audit rate and CP2000 guide.

Processing times and tracking

The IRS says to allow 8 to 12 weeks, and in some cases up to 16 weeks. Where’s My Amended Return? shows status about 3 weeks after filing. Errors, incomplete information and a missing signature can trigger extra review. In El Deeb, the IRS letter arrived only after the deficiency notice.

Checklist for CPA firms

• Pull the wage and income transcript first. Address every information return, even items you think are nontaxable, and explain them in Part II. Our Jackson substitute-for-return post shows how the IRS uses those records.
• Recompute income-based credits. More earned income can reduce the EITC.
• Check claimed payments against the account transcript.
• E-file when allowed and follow up at 3, 12 and 16 weeks; keep proof of mailing for paper.
• Diary the §6511 deadline and, if a notice of deficiency arrives, the petition deadline, even with an amendment pending.
• Corrected W-2s: see our W-2c and 941-X quick read.

Where this fits for Tax Brew readers

Amended returns are detail work: matching transcripts, recomputing credits and following up. Tax Brew provides outsourced bookkeeping and tax prep support to US CPA firms. Email info@taxbrewglobal.com.

Check current IRS guidance: this article summarizes El Deeb v. Commissioner, T.C. Memo. 2026-101 (Docket No. 4398-24, filed September 29, 2026); IRC §§6211(b)(1) and 6511 and Treas. Reg. §1.6664-2(c) (Cornell LII); the IRS pages “File an amended return,” “Where’s My Amended Return?” (updated October 13, 2026), Topic No. 308 (updated September 24, 2026) and “Understanding your CP2000 notice” (updated July 14, 2026); and the Instructions for Form 1040-X (December 2025). General information, not tax or legal advice. Sources as of 14 October 2026.