Breaking a decades-long tradition, Donald Trump will not release his tax returns before voters head to the polls on Nov. 8, the Republican presidential nominee's running mate confirmed Sunday.

In an appearance on NBC News' "Meet the Press," Indiana Gov. Mike Pence reiterated that Trump will not release his returns until after an audit is completed.

"All right, so not before the election?" host Chuck Todd asked.

"Yeah," Pence said.

Trump has declined to release his returns over the course of the election, citing an ongoing IRS audit. The IRS has said that being under audit does not bar a person from releasing his or her tax information.

Pence in September released a decade's worth of tax returns. Democratic presidential nominee Hillary Clinton and her running mate, Virginia Sen. Tim Kaine, have released nearly 10 years of tax returns.

The Tax History Project compiles tax information from former presidents and recent presidential candidates. The Project lists tax information for all Republican presidential nominees over the past nine elections with the exception of Bob Dole. A 1996 article from the New York Times shows Dole released his tax returns as well.

Presidential nominees are not required to release tax information.

According to the Sunlight Foundation, a nonprofit organization focused on government transparency, tax returns can provide insight into a candidate's values and spotlight his or her potential conflicts of interest.

"There is a reason why banks use tax returns when evaluating mortgages: the forms offer a snapshot of a person's financial position and their financial decision making processes," the Foundation wrote in July.