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  • Writer's pictureJonathan Cunningham, CPA

Navigating Uncertainties in Tax Returns: The Concept of "Best-Efforts"

Tax returns need to be precise, but sometimes financial records are missing or incomplete. When this happens, a "best-efforts tax return" comes into play. It means making reasonable estimates and doing your best when documents are missing.

Legal Precedent

While there is no mention of “Best Efforts” in the Internal Revenue Code, this topic has been addressed by the courts. 

In the landmark case Commissioner v. Zellerbach Paper Co., 293 U.S. 172 (1934), the Supreme Court emphasized that the Internal Revenue Service (IRS) can accept a return based on estimates, given they are reasonable and made in good faith. This ruling acknowledged the practical challenges faced by businesses in maintaining comprehensive records and endorsed the use of reasonable estimations in such circumstances.  From the court's published ruling:

Perfect accuracy or completeness is not necessary to rescue a return from nullity, if it purports to be a return, is sworn to as such . . .   and evinces an honest and genuine endeavor to satisfy the law.  This is so even if at the time of filing the omission or inaccuracies are such as to make an amendment necessary.

Another case, Badaracco v. Commissioner, 464 U.S. 386 (1984), further underscores the relevance of best-efforts tax returns. The court deliberated on the significance of making a diligent attempt to comply with tax obligations, even when faced with uncertainties or missing documents. The emphasis was on the taxpayer's responsibility to act in good faith, exercising reasonable efforts to reconstruct records or provide credible estimates.

The Beard Test, derived from Beard v. Commissioner, 82 T.C. 766 (1984), outlines the requirements for a best-efforts approach. To meet this test, a taxpayer must satisfy four criteria: (1) Must have filed a return that is an honest and reasonable attempt to satisfy the requirements of the tax law; (2) Must have provided sufficient data to calculate tax liability; (3) Must have made an honest effort to assess the proper tax liability; and (4) it must be executed by the taxpayer under penalties of perjury.

How to Handle Incomplete or Inaccurate Tax Information and Missing Documents

When accounting or bookkeeping records are unavailable or key documents missing, taxpayers must proceed with care and thoroughness. The absence of documentation doesn't absolve one from tax liabilities; hence, resorting to estimations becomes necessary. Here are some strategies to navigate this terrain:

  1. Reasonable Estimates - Utilize available information, historical data, industry standards, and any feasible means to derive reasonable approximations for missing figures. Ensure these estimates are justifiable, logical, and supported by any available evidence.

  2. Documentation of Efforts - Maintain a detailed record of the steps taken to reconstruct missing information. This documentation serves as evidence of good faith efforts made to comply with tax requirements.

  3. Professional Assistance - Seek guidance from tax professionals or accountants well-versed in handling situations involving missing data. Their expertise can offer insights into acceptable estimation methodologies and IRS compliance.

  4. Communication with the IRS - If faced with significant uncertainties, consider disclosing this to the IRS. Open communication about missing data or estimations made in good faith can demonstrate transparency and willingness to cooperate.  Consider filing form 8275 with your "best efforts" return to disclose certain positions or results in the tax return.

While these strategies provide a framework for managing missing data, uncertainties in tax returns remain a gray area. "Best-efforts" is not a blanket immunity but rather a recognition of the practical challenges in maintaining flawless records. Taxpayers must exercise due diligence, acting in good faith and applying reasonable efforts to address uncertainties in their filings. It is crucial to strike a balance between providing accurate information and making reasonable estimations when faced with incomplete or missing records. Caution must prevail. Deliberate falsification or negligence in attempting to accurately report financial information can lead to severe penalties. At the same time, disclosure and reasonable estimations can protect from penalties and are usually better than simply failing to file any return.


In conclusion, while striving for accuracy remains paramount in tax reporting, the reality of missing data and documentation sometimes necessitates the use of estimations. Precedent setting cases like Commissioner v. Zellerbach Paper Co. and Badaracco v. Commissioner emphasize the importance of acting in good faith, making reasonable estimations, and maintaining transparent communication with the IRS. The goal should be to submit a return that, despite its uncertainties, reflects the most accurate depiction of the taxpayer's financial position to the best of their ability.



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