I ran a what if 1040 for a family of three making 30K and 40K. The 1000 bonus increased their Fed. tax $175 leaving $875 from the bonus, for non FL CMs it will be different
That is for 2017 income, I presume, not the new 2018 tax laws.
So married with one child. I presume all are US Citizens. No other income, special credits, etc.
At $30,000, the couple owes no tax, and would qualify for refundable Child Tax Credits. ($525)
At $31,000, the couple owes no tax, and would qualify for refundable Child Tax Credits. ($675) Yes, an EXTRA $150
At $40,000, the couple owes no tax.
At $41,000, the couple owes no tax.
As stated earlier, the Federal Withholding ($220) would be returned when the 2019 return was filed, plus the possibility of getting the 7.65% SS/Medicare tax refunded in the Child Tax Credit.
Let's look at a Single person without kids.
At $30,000, Fed Taxes owed are $1,970 before withholding
At $31,000, Fed Taxes owed are $2,090 before withholding, so an extra $120, leaving $100 to be refunded in 2019.
At $40,000, Fed Taxes owed are $3,170 before withholding
At $41,000, Fed Taxes owed are $3,290 before withholding, so an extra $120, leaving $100 to be refunded in 2019.
Plus, the EITC charts are not out, but the Married couple with one child would qualify for the additional refundable amount to just under $41,000. More kids, more EITC. Single parents (Head of Household) would also get back some.
As stated earlier, every person's tax situation is different. Some workers might qualify to be a dependent on someone else's return if they work part-time, such as a college student just working the summer, so this wouldn't apply to them.