Of all the reasons for filing or paying late, this is the one the IRS most readily recognizes. A death in the family, a serious illness, a hospitalization. The manual names them directly.

That does not mean a mention of illness gets the penalty removed. The IRS does not grant relief for grief or sickness in general. It grants relief when the event actually prevented compliance during the period that mattered. Getting from the first to the second is the whole job.

What the manual says

IRM 20.1.1.3.2.2.1 says death, serious illness or unavoidable absence of the taxpayer, or a death or serious illness in the taxpayer's immediate family, may establish reasonable cause for filing, paying or depositing late.

For individuals, the manual defines immediate family as spouse, sibling, parents, grandparents and children. A death or serious illness of someone outside that list is not automatically excluded from consideration under the general ordinary business care standard, but it is not within this specific category, and you should expect more questions.

Notice that unavoidable absence applies to the taxpayer, while death and serious illness also reach immediate family. A spouse's long business trip is not the same as a spouse's hospitalization.

Businesses, estates and trusts

For a corporation, estate, trust or similar entity, the manual applies the rule to the person responsible. Death, serious illness or unavoidable absence of that person, or of a member of that person's immediate family, may establish reasonable cause, but only if that person had sole authority to execute the return, make the deposit or pay the tax.

That last condition does real work. If someone else was authorized to sign or pay, the IRS asks why that person did not. And the manual goes one step further: in a business with only one authorized person, the IRS will consider whether having only one was itself consistent with ordinary business care and prudence.

So a business owner who was hospitalized and was the only person with access to the payroll account has a better argument than one whose controller could have made the deposit but did not. In the second case, the explanation has to cover the controller too.

The seven things the IRS looks at

IRM 20.1.1.3.2.2.1 lists the information to consider. Treat it as your outline:

  • The relationship of the taxpayer to the other parties involved.
  • The date of death.
  • The dates, duration and severity of the illness.
  • The dates and reasons for absence.
  • How the event prevented compliance.
  • Whether other business obligations were impaired.
  • Whether tax duties were attended to promptly when the illness passed, or within a reasonable period of time after a death or return from an unavoidable absence.

Four of the seven are about dates or timing. That is not an accident.

Where these requests fail

The manual gives an example of a request that may fail. A death occurred several months before the due date. The return was not filed until a year after the due date. The death was real. The loss was real. But the timeline does not show the death preventing compliance for the whole period, and the manual says the length of time between the event and later compliance may cancel or reduce the event's effect.

The other common failure is the sixth factor: other business obligations. If you were well enough to run your business, close deals and meet payroll, the IRS will ask why you could not file a return or make a payment. The general reasonable cause questions in IRM 20.1.1.3.2 include how you handled the remainder of your affairs during the period. Your story has to be consistent across everything you did.

This is not the IRS being cruel. It is the IRS testing causation. The question is not whether something bad happened. The question is whether the bad thing is why the return was late.

Building the proof

Match your documents to the factors:

  • For a death: a death certificate or obituary, and something showing the relationship if it is not obvious.
  • For illness: hospital admission and discharge records, a physician's letter describing the dates and severity of the condition and the period of incapacity, or treatment records. You do not need to hand over a full medical file. You need the dates and enough to show severity.
  • For absence: travel records, deployment orders or similar proof of when you left and when you returned, and why the absence was unavoidable.
  • For the aftermath: the date you filed or paid, and an explanation of anything that took time after the event ended.

Then lay it out in date order. The due date, the event, the end of the event, and your compliance. If the dates line up, the request reads itself. Writing a penalty abatement letter covers format.

When the taxpayer is the one who died

Penalty questions often surface after a taxpayer's death, when an executor or surviving spouse discovers late returns. The person responsible for the decedent's final returns may have strong facts: the decedent was ill before death, and the executor did not have authority or records until appointed.

Those facts often overlap with inability to obtain records, and the request should address both. But be careful about the executor's own deadlines. In United States v. Boyle, 469 U.S. 241 (1985), the executor relied on an attorney to file the estate tax return, and the attorney missed the deadline. The Supreme Court held that reliance on an agent to file is not reasonable cause for a late filing. The executor's own duty to know and meet the deadline did not move to the lawyer.

Caring for a family member

Many requests involve not the taxpayer's own illness but the illness of a parent, spouse or child the taxpayer was caring for. The manual's category covers serious illness in the immediate family, so this is squarely within it.

The same proof applies, with one addition. Show what the caregiving actually required of you. Moving into a parent's home for three months of hospice care, or spending weeks at a child's hospital bedside, is a concrete account of why your own affairs went unattended. A general statement that a relative was ill is not.

Show too what happened after. If the illness ended in a death, the manual expects tax duties to be attended to within a reasonable period after the death. Grief is real, but an unexplained year of silence afterward will undercut a strong case about the months before.

Long illness and the limits of the doctrine

In Boyle, the Supreme Court noted that its holding did not address a taxpayer who was, by objective standards, incapable of meeting the ordinary business care and prudence standard, and said that in such a case the disability alone could well be an acceptable excuse. A concurring opinion joined by four Justices emphasized the same open question.

That language does not create a rule. It does tell you why a well-documented incapacity, as opposed to an inconvenient illness, is the strongest form of this argument. If a medical condition truly left a person unable to manage their affairs, say that, prove it, and show who stepped in and when.

The rule of thumb is simple. Prove the event. Prove the dates. Prove that you acted when you could. If your history is clean, also check first-time abatement, which needs none of this.