My average deduction is $46k per yr. With new tax laws of $24k standard deduction for married filing jointly, what can I expect when I file my taxes? Will I owe $22k??

If your average Itemized deductions on Schedule A are currently about $46k then your average Itemized deduction on Schedule A for tax year 2018 will be about the same amount.  Although certain itemized deductions have been reduced or eliminated.

What are you calling a deduction? There are many types. The three basic types for 2017 are the standard deduction, the self-exemption for tax filers and the dependent exemption if the tax filers have dependent.
For 2018, the self-exemption and dependent deductions are no more. They no longer exist. But the standard deduction for each tax filer has almost doubled.
Many are upset with the current tax changes as passed by congress and signed into law by President Trump, which kicked in on Jan 1, 2018. This is understandable for those that have more than 2 children. Without the changes in 2018 you would have been able to deduct $4,100 from their taxable income for each qualified dependent. But for those that have only one or two children, they haven't done the math, and therefore believe it won’t make a positive impact. But looks can be (and are in this case) deceiving. Let’s look at the math both ways, starting with the old way which we’d be doing had the changes not passed. Let’s use a married couple filing a joint return with two children, one age 11 the other age 17 on Dec 31 of 2018.
The old way:
For a married couple filing joint, their standard deduction is $12,800. Then each parent also gets a $4,100 personal exemption bringing the total of tax free income thus far to $21,000. Now add to that a dependent exemption of $4,100 for each child bringing the final total to $29,200 that our family of four can deduct right off the top of their taxable income.
The new way:
Same married couple with same two children now only gets a $24,000 standard deduction for a married couple filing joint. That’s it. So this couple will be taxed on an additional $5,200. Yeah, that sucks I know, and I agree. But do the math and you’ll be quite pleasantly surprised. You have to look at the new tax rate and tax bracket structure too, because that plays into this quite heavily.
Let’s consider in our two examples above that the combined gross income of both parents was $160,000 for the tax year.
With the deductions outlined above under the old way, they would be in the 28% tax bracket. The taxable income after the standard deduction and dependent exemptions would be $130,800. Tax liability on that taxable income would be $29,606
Under the new way the parents are in the 22% tax bracket. They can only deduct the standard deduction of $24,000 from their $160,000 gross income, bring their taxable income to $136,000. Their tax liability in the new lower 22% tax bracket will be $21,799.
That’s a tax savings of $7,807 in *FAVOR* of the taxpayer.

What type of Schedule A itemized deductions do you have that add up to that much?

How will tax reform affect my 2018 federal tax return?

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