The Congressional Budget Office informed Senate Budget Committee Ranking Member Jeff Merkley (D-Ore.) in a letter Monday that the One Big, Beautiful Bill Act, President Trump’s signature domestic policy accomplishment, would add $5 trillion to the deficit over the next decade if its temporary tax relief provisions are extended for a full 10 years.

The budget office projects that if temporary tax relief provisions, such as the tax exemption on tipped wages up to $25,000 and the $6,000 senior deduction, are made permanent, it would add another $789 billion to the debt over the next 10 years.

That and $718 billion in debt-servicing costs bring the total price tag for Trump’s “big, beautiful bill” to nearly $5 trillion over a decade.

The CBO estimates that as a result, the total amount of federal debt held by the public would increase by 11.5 percentage points by the end of 2034.

“Each and every analysis from the nonpartisan Congressional Budget Office continues to show the same result regardless of how you look at it: this bill explodes the debt by trillions of dollars to fund tax breaks for billionaires,” Merkley said in a statement.

“It is the height of hypocrisy coming from the party that claims to be fiscally responsible,” he said.

CBO produced its estimate in response to Merkley’s request asking for the budgetary impact of making 10 provisions in Trump’s domestic policy law that are due to sunset in the next few years.

They include the senior deduction, the tax exemption for tipped income, the tax deduction on overtime income up to $12,500 for individuals and $25,000 for joint-filers, and the tax deduction on auto loans for new cars made in the United States.

The CBO noted to Merkley that the Joint Committee on Taxation has estimated that making those 10 provisions permanent would increase primary deficits over the 2025–2034 period by an additional $789 billion.

“That change would increase the cumulative effect on the deficit to $5.0 trillion,” the CBO wrote to Merkley.

“As a result, and net of any changes in borrowing for federal credit programs, CBO estimates that debt held by the public at the end of 2034 would increase by 11.5 percentage points relative to the agency’s January 2025 projection of GDP,” it estimated.