We make a fair bit less than Wrecks, but using some online calculators (of uncertain accuracy), I estimated this plan will cost us over $20K per year with the loss of SALT and capping of property tax deductions and there isn't much in the way of marginal rate reduction to offset.
We have to be careful about what we're talking about. Are you paying $20k in extra taxes, or are you losing $20k in deductions (and thus paying $5k in extra taxes at 25% on that 20k)?
Someone asked for numbers? A family like mine, with two parents and three kids and a house, could previously claim 20k in personal and dependent exemptions, plus 10k in mortgage interest, plus 5k in property taxes, plus about $1k in sales tax (my state takes the sales tax deduction instead of the state income tax deduction), plus whatever you donate to charity. So that was previously an easy $36k of tax-free income before even touching your 401k contributions.
The new plan keeps the mortgage interest but repeals all of the rest, so this family will only be able to itemize 10k instead of 36k. That means they will have to take the new 24k standard deduction. 24k is 12k less than the 36k they were sheltering the previous year, so they'll pay 25% taxes on that extra 12k of income, or a $4k tax increase.
The child tax credit would erase $3k of that $4k, at least for the first few years until it is scheduled to phase out. The changes in the brackets would also save us a few hundred. The net effect is that our taxes should only go up by a few hundred dollars per year, next year, but then much more in later years as the child tax credit is phased out and the new lower inflation adjustments kick in to force down the brackets.
But think about all of the secondary effects of this new plan. Charitable deductions are no longer deductible, so charities will receive less. Whatever happend to "compassionate conservates"? Mortgage interest is technically not revoked, but since all of the other deductions and exemptions are revoked the mortgage interest one is worthless unless you have more than 24k of mortgage interest, which restricts it to a very narrow band of people who live in high tax states and own home between about 700k and 1mil dollars. State sales and income taxes lose their deductible status, which has a whole long list of add-on effects that I'm still working through but which don't look good for anyone. I don't think Republicans, or anyone else really, has spent the time to think through all of these repercussions. It will be an interesting next few weeks as all of this comes to light.