US President Joe Biden and First Lady Jill Biden publicly released their 2023 tax return on Monday, carrying on a tradition of transparency temporarily interrupted under predecessor Donald Trump.

The annual, unwritten custom is designed to build trust in the White House. Other politicians as well as candidates often also take part.

The Bidens earned $619,976 in 2023, most of which was derived from the president's $400,000 salary and Jill Biden's $85,985 compensation for her teaching job at a college in nearby Virginia.

That number was up from the $579,514 the couple earned in 2022 and $610,702 in 2021.

The Bidens' transparency comes after Trump opted not to follow the bipartisan tradition.

Billionaire businessman Trump refused both as a candidate and once in office to allow the public to see his tax return, a document detailing all sources and amounts of income, among other financial records.

When several years of his returns were finally made public after a legal battle waged by Democrats in Congress, it emerged there were years when Trump was paying almost no income tax, due to business losses.

He has continued to keep his tax returns private as he wages his 2024 campaign to return to the White House.

The Bidens reported paying $146,629 in federal taxes, for an effective rate of 23.7 percent.

Joe Biden also reported paying $30,908 in Delaware income taxes, while Jill Biden paid $3,549 in Virginia income taxes.

"President Biden believes that all occupants of the Oval Office should be open and honest with the American people, and that the longstanding tradition of annually releasing presidential tax returns should continue unbroken," the White House said in a statement.

It said this year marked the 26th year of Biden sharing his tax returns publicly.

The Bidens also reported $20,477 in charitable donations.

Vice President Kamala Harris and husband Doug Emhoff also released their tax returns, showing $450,299 in income and $23,026 in charitable donations.

They paid $88,570 in federal income tax in addition to $15,167 in California income tax and $11,599 in District of Colombia income tax.