Upon returning home from class, a University of Rhode Island professor finds his house on fire — and some tax records damaged or destroyed.

The fire that occurred last month at the home of Joseph P. Matoney in South Kingstown is the sort of disaster that could happen to anyone, said Gregory A. Porcaro, former president of the Rhode Island Society of Certified Public Accountants.

And while the ruin of important tax-related documents pales in comparison to other types of loss that people suffer at such times, a question nevertheless arises: What can a taxpayer do, especially if the disaster occurs during tax-filing season?

First, know that you are not alone. Losing key tax documents is “not as uncommon as people think,” Porcaro said in an interview at Otrando, Porcaro, & Associates Ltd., a CPA firm in Warwick, where he is tax partner.

“We’ve had a lot of clients over the years who’ve had a flood, a fire. . . . It could be just a pipe that bursts,” flooding a basement and destroying vital records stored there, he said.

When a catastrophe is widespread, such as Hurricane Katrina, the government intervenes, providing relief from the usual rules for thousands of taxpayers.

But even in individual disasters, a taxpayer may follow certain steps, and take advantage of some special rules, in the struggle toward recovery, said Bob D. Scharin, RIA senior tax analyst from Thomson Tax & Accounting of New York. For example:

•Deadline: In general, you’re required to file a return each year and pay whatever tax you may owe. If you don’t, you could face penalties plus interest, said Internal Revenue Service spokeswoman Peggy Riley.

But the mid-April deadline is not hard and fast; you may obtain a six-month extension, pushing the deadline back to mid-October. This will give you an additional six months to file, and some breathing room as you try to rebound, Riley said.

You don’t need a reason; the extension is automatic, provided you take the appropriate step, such as filing Form 4868. (This year’s filing deadline is April 17; a six-month extension would push the deadline back to Oct. 15.)

Just remember that, for federal and Rhode Island tax purposes, it’s only the filing deadline that gets extended, not the payment deadline.

If tax is due, you still must pay what you owe by the mid-April deadline, or make some other arrangement by then, such as an agreement to pay in installments. Otherwise, you may have to pay penalty plus interest, Riley said.

•Basic Records: How can you pay what you owe when your records have been lost or destroyed?

In general, the loss of such records represents “a big inconvenience,” but most documents can be reproduced, Porcaro said. "It’s not the end of the world, but it can be a pain in the neck,” he said.

For example, if you’re missing a Form W-2 wage statement, you probably can get a duplicate from your employer, said Scharin, whose company provides tax information and software to tax professionals nationwide.

If you don’t receive a copy in time — either for the mid-April deadline or the extended deadline — your final paycheck of the year might contain the information you need.

If that’s not available, file Form 4852, “Substitute for Form W-2, Wage and Tax Statement," and attach it to your return.

On that form, estimate the amount of your income and withholding taxes as accurately as possible. (There may be a delay in processing your return while the IRS verifies the information, Riley said.)

If you’re missing Form 1099 interest statements from banks and credit unions, or Form 1099 investment statements from brokerages and mutual-fund companies, you probably can obtain printed duplicates from the financial institutions, or print out the necessary paperwork from their Web sites.

If you can’t get the required copies on time, try to obtain the figures you need from documents you received late last year or just after the year ended, such as a year-to-date summary from your bank, investment institution or lender, Scharin said.

•Deductions: To claim a deduction, you typically must have records on hand to serve as proof should you later be subject to IRS examination.

What if your records have been destroyed in a calamity? Here, again, copies can help. For example, if you plan to deduct interest on a home mortgage loan, your lender probably can supply a duplicate of the statement it sent you at tax time. You might also be able to rely on the periodic statements it sent you throughout the previous year.

If you made a large charitable contribution, chances are the charity can supply you with a copy of the letter it sent you confirming the date and amount of your contribution and other details.

If you plan to deduct amounts you paid for college tuition and fees, your educational institution should be able to give you a copy of the form it sent detailing the amounts you spent, Porcaro said.

•Record Reconstruction: In some cases, obtaining the required records may not be easy.

For instance, what if you donated some clothing, and the only record of the contribution was lost or destroyed? The general rule is that “anything you can’t substantiate can be disallowed,” Porcaro said.

What to do? In such cases, you may have to reconstruct records or rely on other records and good-faith estimates; the IRS may find that acceptable, given the circumstances, said Mark Higgins, dean of the University of Rhode Island’s College of Business Administration.

For example, if records of hard-to-document charitable contributions have been destroyed, the IRS might approve an estimate based on your contributions from previous years, provided that you supply the necessary paperwork, Porcaro said.

U.S. Treasury regulations put it this way: "Where the taxpayer establishes that the failure to produce adequate records is due to the loss of such records through circumstances beyond the taxpayer’s control, such as destruction by fire, flood, earthquake, or other casualty, the taxpayer shall have a right to substantiate a deduction by reasonable reconstruction of his expenditures or use.”

As long as what your estimates are reasonable and you can explain the situation, “I think you would be all set,” said Higgins, the URI business-school dean.

The important thing is to make a good-faith effort. If you can’t determine the exact amount of an expense, for example, you still must make your estimate as accurately as possible, using all available records.

This point was underscored by a U.S. Tax Court case involving Dennis A. Fortin, of Coventry, and Elinor N. Fortin, of Ludlow, Vt.

As part of their poultry business, the couple bought some chickens, but later discovered that some of the chickens were ill.

The couple claimed a $6,900 deduction. Mrs. Fortin testified that the paperwork to substantiate the deduction was destroyed in a fire which caused substantial damage to the poultry and much of the farm buildings and equipment.

But the court, in a 1989 decision, disallowed the deduction. It found that the couple made no effort to obtain substitute documents to verify the expense, and had not made any effort to obtain verification through the poultry supplier.

Fortunately, most deductions these days may be substantiated through third parties, Porcaro said. That’s because, as a general rule, most transactions are recorded — somewhere — electronically.

It may cost you — in time and money — to search for and obtain the necessary documentation, but at least the information is often available, he said.

•Penalty Waiver: If you can’t pay what you owe on time, the IRS may be willing to waive any penalties that would otherwise apply, provided you can show that your delinquency is due to reasonable cause beyond your control, Scharin said.

“The IRS is not heartless,” and will generally be willing to work with you in such circumstances, said Higgins.

But to plead your case before the IRS, for such things as penalty waivers, good-faith estimates or best-effort record reconstruction, you first need to document the problem itself.

So to help prove that a disaster occurred, be prepared to produce a copy of the relevant police or fire report and any insurance claims you may have filed, Porcaro said.

•Business Records: Obtaining third-party verification can be much more difficult for business-related records, partly because “You’re going to have a lot more to deal with,” Porcaro said.

A business owner may have to reconstruct business records from scratch, using invoices, deposit slips, canceled checks and such. A business, remember, engages in a variety of transactions with multiple parties, including customers, vendors, employees and others.

One place to start is with invoices from suppliers, which can help document expenses, said Riley, the IRS spokeswoman.

Also obtain copies of bank statements — the deposits should closely reflect what the sales were for any given period, she said.

In addition, get copies of the most recent year’s federal, state and local tax returns. These can also help to show gross sales for a given time period, or provide a basis on which to calculate estimates, she said.

A business’s computer software program can be a big help, too, but only if the program itself wasn’t destroyed.

A number of businesses routinely back up its data off-site, Porcaro said. (Some computer software programs may be set to routinely transmit data to another location, such as a data-storage facility.)

The point is that the IRS will want documents to detail, as accurately as possible, the business’s income and expenses.

If all records — including computerized records — have been destroyed, the IRS may accept estimates, perhaps based on the business’s prior-year financial results.

•The Cohan Rule: Another option is to invoke the Cohan Rule. It emerged from a tax case involving George M. Cohan, the well-known theatrical manager and vaudeville star.

Cohan spent substantial sums on travel and entertainment (including the entertainment of drama critics), and claimed deductions. But the IRS disallowed the deductions because he had no records.

Cohan pressed his case to the U.S. Court of Appeals for the Second Circuit — and, on the issue of deductions for travel and entertainment expenses, he won.

The eminent jurist, Lerned Hand, declared, “Absolute certainty in such matters is usually impossible and is not necessary; the [government] should make as close an approximation as it can bearing heavily if it chooses upon the taxpayer whose inexactitude is of his own making. But to allow nothing at all appears to us inconsistent with saying that something was spent.”

The case was decided in 1930. Some laws enacted since then have limited the Cohan Rule’s applicability, Scharin said. Nevertheless, taxpayers continue to cite it, sometimes successfully.

ndowning@projo.com