A newly discovered letter by Thomas Jefferson shows ‘a regular guy with financial burdens’

He came from one of America’s wealthiest landowning families, and was ranked the fourth richest US president in a recent study. But Thomas Jefferson, the nation’s third president, harbored a secret during his time in the White House: he was almost constantly in penury, and struggled to pay his food bills, servants and other household expenses.

The revelation comes in a previously unpublished letter that Jefferson, who was president from 1801 to 1809, wrote to a friend who acted as his financial agent in October 1802.

The document, valued at $40,000, is for sale by Pennsylvania dealer the Raab Collection to commemorate the Fourth of July holiday, also the 198th anniversary of Jefferson’s death.

That Jefferson, a founder and primary author of the Declaration of Independence, died broke is not new. Like many plantation owners of the period, he struggled to balance the books, and left a debt of $107,000 (more than $1m today) that led heirs to sell his possessions, including slaves and his beloved Monticello estate in Virginia.

The letter shows the degree to which financial problems were constantly on Jefferson’s mind during his time in the Oval Office. The missive to English-born tea merchant John Barnes, Monticello’s accounting manager while Jefferson was in Washington DC, urges him to express frugality with limited resources, intending to stave off making a request for another bank loan secured against his future presidential earnings.

The pair had already exchanged correspondence through the spring and summer of 1802, with Jefferson calculating how to trim household expenses. The newly revealed letter indicates that he was trying to figure out how to stretch the money he did have until the following March.

“This letter is a remarkable historical discovery,” said Nathan Raab, president of the Raab Collection.

“We can see in it Thomas Jefferson not as an unapproachable president, but as a regular guy with financial burdens and worries, just like the rest of us.”

The letter, Raab said, was noted as missing in Princeton University’s definitive chronicle of Thomas Jefferson papers.

“In other words, scholars knew the letter once existed but thought it had been lost,” he said.

Related: Public artwork reframes US history of enslavement through Jefferson’s valet

“Long in private hands, it escaped the notice of 20th century cataloging projects and thus has not been seen or studied by scholars.”

Raab said he acquired it earlier this year from the family of “an American collector” who bought it in 1929 from Thomas Madigan , a prominent New York collector of historical memorabilia, two years before Madigan’s death.

Previous notable sales by Raab include one of the last letters signed by Abraham Lincoln , which was hidden in a desk drawer for years; and a signed note from Les Misérables author Victor Hugo urging its unnamed recipient to donate generously towards “the poor of your country”.