Could tax cuts proposed pay for themselves? The Tax Foundation crunches the numbers for us.

"...what kind of growth would be necessary for a tax cut to be completely self-financing? So let’s take President Trump’s stated goal of a 15 percent corporate income tax cut as an example and run some quick back-of-the-envelope math with round numbers to illustrate the basics of how this might work...

The short answer is you’d need about 0.9 percent additional growth over the 10-year budget window that is commonly used in Washington D.C. for budget bills. By “additional growth,” I mean over and beyond what forecasters typically predict...

Tax Foundation’s Taxes and Growth model would not predict 0.9 percent added growth over the budget window from a corporate rate cut to 15 percent. We’ve run this particular scenario before as Option #51 in our book, Options for Reforming America’s Tax Code. The model predicts something more like 0.4 percent over the budget window: a sustained period of 2.3 percent growth instead of 1.9 percent growth, until the economy is eventually about 4 percent larger.

Other macroeconomic models used for tax policy, such as those used at Tax Policy Center or at the Joint Committee on Taxation, would also not likely predict that much growth from that 15 percent tax cut."

—Alan Cole, Tax Foundation