Donald Trump made at least 10 new tax cut promises. Can he keep any of them? (Video)

It was last week, during a campaign stop, that – for the second time in as many days – Donald Trump revealed a new and potentially expensive tax promise.

The topic of the day was a call to make interest on car loans fully tax deductible. The day before, he promised another cut for Americans living abroad.

The two proposals were, by Yahoo Finance’s count, at least the ninth and tenth separate tax cut promises that Trump has made in recent months. They include his calls for a full extension of the 2017 tax cuts with modifications and a series of add-ons, such as eliminating taxes on tips, overtime and Social Security benefits.

But he has offered few ideas to pay for it and could face opposition even from his own party in approving them if he wins.

As for the cost of all these promises, the closest thing to a total bill comes from the Committee for a Responsible Federal Budget (CRFB). Finds that Trump’s tax promises could cost more than $9 trillion over the next decade.

But this total still does not include the two new proposals released last week, as well as other promises that do not have enough details to be calculated.

Kamala Harris, of course, has her own tax cut ideas, but the scale of Trump’s promises is remarkable.

The list was met with a combination of shock and dismissive looks from tax experts, but critics did little to dissuade him from regularly unveiling new proposals and offering the promised new benefits directly to the most interested groups of voters.

Trump is also promising a significant tax increase (though he would never call it that) in the form of a new wave of tariffs that experts say could add thousands of dollars to U.S. household budgets. Tariffs are taxes paid by importers at points of entry into the U.S., with additional costs often passed on to consumers.

Here’s a quick summary of Trump’s many promises and the many challenges they would face before becoming law:

Promises for significant electoral blocs

Many of Trump’s ideas are clearly intended to appeal directly to the blocs he needs to win in November.

“Do we have anyone who works in restaurants?” he asked a recent crowd in Reading, Pennsylvania, before reiterating his promise of no taxes on tips. Likewise, his latest car loan idea was revealed in Motor City, also known as Detroit.

When the audience includes seniors, their focus shifts to removing taxes on Social Security benefits. Trump’s plan would cut off the program’s funding source and has raised concerns that it could produce an even faster decline in the safety net program.

In fact, these specific proposals have, in addition to their cost, also been criticized by economists for potentially distorting incentives if, for example, tips or overtime are not taxed but regular wages are.

A recent analysis by the Yale Budget Lab focused on how implementing these ideas would increase “horizontal inequalities” in the tax system. In other words, two people earning the same amount of gross salary could pay very different taxes depending on whether or not their compensation includes tips or overtime.

Democrats were even less kind. “These tax proposals he is pushing out of desperation are as fake as his tan,” Senate Finance Committee Chairman Ron Wyden said in a statement. “Trump knows that Republicans in Congress have no intention of passing this thing, but he goes ahead and lets it slip anyway.

Trump weighed in on the key 2024 issue of housing affordability by unveiling a Republican Party platform that promises to “promote homeownership through tax incentives and support for first-time buyers.” This is an idea that the CRFB estimates could cost between US$100 and US$350 billion if implemented.

Trump’s latest targeted promise is to make car loan interest work similar to the current mortgage interest deduction for homeowners.

“We’re going to make interest payments fully deductible,” Trump said when unveiling the idea, saying it would revolutionize the auto industry and comparing the idea to the invention of the paperclip.

Trump’s other new promise is the elimination of “double taxation” for Americans living abroad.

“You have to make sure you’re registered and that you’re going to vote, because I’m going to take great care of you,” Trump promised the public in a web video.

A series of promises linked to an upcoming tax debate in 2025

Trump also made a broad series of promises directly tied to the Tax Cuts and Jobs Act of 2017. These tax changes that Trump himself signed into law came with an expiration date on key provisions at the end of 2025.

The GOP nominee pledges to fully extend the expired provisions of these tax cuts. It is his most cherished promise and one that he repeats at almost every stage of the campaign, but which his allies on Capitol Hill may be abandoning.

This 2017 law also reduced the federal corporate tax rate to 21%. Trump now wants an even lower value and has settled on 15%, calling it the “Made in America tax credit.” It’s a rate he previously feared was too low and another front where his party might not fully support him.

Trump also pledged to reverse a separate provision of the 2017 law that imposed a $10,000 cap on state and local tax (SALT) deductions. That cap was included at the time to help offset some other costs, but it is deeply unpopular in coastal — and often Democratic-run — states with higher local taxes.

Trump revealed this idea in (elsewhere) New York, where anti-SALT sentiment runs deep.

Finally, Trump teased unspecified additional cuts “for working families” as part of next year’s tax negotiations, but did not offer any additional details.

All of this results in a huge list of commitments that goes beyond the limits of even presidential campaign promises.

Vice President Harris is making a lot of promises of her own. Like Trump, she promises no taxes on tips, as well as tax credits for homebuyers.

She is also expected to push for a limited extension of the 2017 tax cuts, but will allow provisions for Americans earning more than $400,000 to expire.

According to the CRFB, it is likely to increase debt by $3.5 billion by 2035. President Trump’s ideas, however, would mean much more: $7.5 billion in new red ink.

And Trump ended his promises? That seems unlikely, with about three weeks left until voting and many campaign stops ahead.

One big possibility: an expansion of the child tax credit that Harris has made a centerpiece of her campaign and Republican vice presidential nominee J.D. Vance has expressed support for the expansion.

Since Vance’s comment in August, Trump has, according to advisers, been considering supporting “significant expansion” in that country.

Ben Werschkul is the Washington correspondent for Yahoo Finance.

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