"Project 2025" is not being featured on the main stage of the Republican convention this week, but a active debate about it on the sidelines could still shape the GOP approach to taxes.

That, in turn, could influence how much you and America’s biggest companies pay to Washington in the years ahead.

The sprawling 922-page "Project 2025" was developed by the influential Heritage Foundation and includes a range of plans, including ideas that would dramatically pare back America’s progressive income tax system and shift some of the tax burden onto lower-income Americans.

The document also outlines novel ideas that could gain attention and move beyond conservative tax circles in the months ahead, including a plan for tax-sheltered "universal savings accounts."

At their convention this week, many Republicans sought to focus on their much shorter party platform. That 16-page document promises to make the 2017 Trump-era tax cuts permanent but offers few additional policy details.

But Heritage's efforts were also very much in evidence in Milwaukee and have been a keen focus of political observers after a calamitous debate performance from President Joe Biden and other recent developments seemed to increase the odds of a second Trump term.

Republicans are also seeing their chances improve when it comes to gaining seats on Capitol Hill, which would be crucial to implementing their agenda.

Paul Dans is the executive director of Project 2025. He has also been a prominent presence this week and helped lead a six and a hour hour "Policy Fest" put on by Heritage on Monday.

The goal of the Project 2025 is to "bring our movement together," Dans said as the gathering kicked off.

Blueprint for 'a new conservative President'

The project began two and a half years ago as an ambitious effort to both outline detailed policy plans and also compile pre-vetted lists of conservative loyalists ready to quickly staff "a new conservative President," as the Project 2025 book puts it.

The plan is also being eagerly promoted by Biden and his allies for what they call "dangerous" ideas it contains on a range of issues from abortion to reshaping the workforce of the federal government.

"The last thing we need is a president who spent four years in office putting corporations first and the rest of us last, getting back into office to repeat the process on steroids," Wisconsin Democratic Party Chair Ben Wikler told reporters this week, also on the sidelines of the GOP convention.

Trump has distanced himself from the effort and called some of the ideas "absolutely ridiculous." However, the effort is run by close allies of the former president who could have prominent roles in a second Trump administration.

On the campaign trail, Trump has been silent on many of these tax ideas. But the proposals are top of mind among many in the party, including Stephen Moore, a top Trump confidant who co-authored the tax section.

In an appearance this week on Yahoo Finance's Opening Bid podcast, Moore focused mostly on criticizing Biden plans when the subject turned to taxes.

"We vastly simplified the tax code," he added of the Trump-era tax cuts he helped get enacted in 2017, saying he felt the move had positive economic effects.

"I'd like to see some further cuts," he said of his own preferences.

Moore offers a much more detailed plan in the Project 2025, where he proposes taking things much further both in terms of GOP efforts to simplify and further cut.

A critical eye to America’s progressive income tax system

The plan was first published as a book back in 2023, and the section on tax policy that begins on page 695 was authored by Moore, William Walton, and David Burton.

It puts forth an overall case that the tax code needs to be simplified and taxes lowered to promote economic prosperity and fund a "limited" government.

Moore is a particularly influential figure in Trump’s orbit. He advised Trump throughout his presidency and was nominated in 2019 to serve as a governor of the Federal Reserve, but his candidacy was stalled by bipartisan resistance in the Senate.

Perhaps the most far-reaching idea in the Project 2025 proposal would dramatically scale back America’s progressive income tax system.

America currently has seven tax brackets and a complex web of deductions and individual credits. That would be replaced by just two rates in this plan — 15% and 30% — as well as a rewritten tax code "that eliminates most deductions, credits and exclusions."

The 30% rate would kick in at $168,000 — to coincide with the point when payroll taxes for Social Security and Medicare stop. The idea is to create essentially a flat tax: 15% plus payroll taxes for wages under $168,000 — and then 30% for those above.

The effect of such a change would clearly be a simpler April filing season for everyone.

But it would also mean a tax increase for less well-to-do Americans who often pay well below 15% and benefit from many existing deductions. The richest Americans currently pay a rate of 37% and so would be likely to see their tax bill decrease.

The left-leaning Center for American Progress has analyzed the plan and estimated that a middle-class family with two children and an annual income of $100,000 would pay $2,600 in additional federal income tax under the plan.

On the other side of the income spectrum, a married couple with two children and earnings of $5 million would enjoy a $325,000 tax cut, the group estimates.

The plan would also implement a tax cut for corporations with a repeal of Biden-era taxes on stock buybacks and financial statement income.

It would also reduce the corporate tax rate — which it describes as America’s "most damaging tax" — to 18% from its current level of 21%.

Trump has offered similar ideas from a recent proposal of a 20% rate when speaking to CEOs to a 15% rate in a Bloomberg interview published this week, while acknowledging of that lower rate "I think that would be, you know, that’d be hard."

A novel new idea: Universal savings accounts

Project 2025 also includes an array of lesser-publicized but nonetheless intriguing ideas that could reshape America’s relationship with taxes and savings.

One such idea would allow taxpayers to put aside money in an account that would then grow tax-free and could be withdrawn at any time.

"The tax treatment of these accounts would be comparable to Roth IRAs," reads the plan.

In a recent conversation with Yahoo Finance, Heritage Foundation budget expert Richard Stern brought up the savings account idea as one that is actively under discussion within the group and could perhaps be a backup plan of sorts if there isn’t an appetite for other higher-profile tax efforts.

If other ideas don't prove politically palatable, Stern asked rhetorically, "can we channel some of that into getting these investment accounts?"

Stern notes that the savings idea might be more popular than cutting corporate taxes and is "a way of alleviating some of this pressure where it really helps low- and middle-income families to save."

'A hot topic'

Project 2025 has plenty of other concepts clearly top of mind among many Trump allies who could be in a position this time next year to make policy.

There are business-friendly ideas to make temporary business tax credits signed into law by Trump in 2017 permanent, as well as to limit taxes on business losses.

There are also ideas to lessen the "tax bias against wages" and implement a cap on what benefits employers can offer without taxes.

The plan also mentions an idea that has been floating around conservative circles for years: a national sales tax.

The document also takes aim at the Internal Revenue Service, calling it an "increasingly politicized agency."

Tax collectors have been the target of GOP ire for years, especially after Joe Biden signed into law a wave of new funding for the agency to go after tax cheats.

Without calling for the abolishment of the IRS — as some conservatives have done — the plan calls for cultural and management changes while revoking that $80 billion in additional funding.

Which of these ideas will advance beyond the pages of this document very much remains to be seen.

For now, Stern said, "I wouldn't necessarily bet" on things like universal savings accounts "being a hot topic" at the remainder of this week's convention or in the campaign to follow.

But the ideas are clearly positioned for a close look in the months ahead if there is indeed a second term for Trump.

Ben Werschkul is Washington correspondent for Yahoo Finance.

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