I was looking at our 2025 tax return (married, filed jointly) and we owed additional $1879 in federal tax. Because of that, we also got vouchers for quarterly tax payments for this year. I could not understand how the amount on each voucher was calculated. Here’s our details:
Total tax – $68869
Total payments – $66990
Payment due – $1879
Quarterly voucher amount – $2192
Where did this $2192 figure come from? Do they think that I may owe $8768 ($2192*4) additional taxes this year?
How is the quarterly tax owed calculated by IRS?
byu/-HoldMyBeer– intax
Posted by -HoldMyBeer–
4 Comments
The software you used make the vouchers, not the IRS. Software often over shoots, as customers think software is good if they get a big tax refund.
You do not have to use those vouchers or those calculations.
You calculate these to meet one of the safe harbor amounts. This is not something the IRS calculates. If you don’t meet one of the safe harbor rules (looking back), then there is a penalty. IRS calculates the penalty, or you can when you file your final return. So what you pay throughout the year and how you do that is up to you, but if you don’t meet certain total amounts, and certain timeliness requirements, you’ll pay a penalty ultimately.
The common safe harbor rules are to pay 100 or 110% of last years tax (depends on how large your AGI is), or 90% of this years tax either by withholding or through estimated tax. If by estimated tax, there is generally no timeliness concern. If estimated tax, then it needs to be paid in 4 equal quarters OR you may have to show your payments were timely using the Annualized Installment Method, which frankly is a lot of work.
I ignore the huge amounts the software says to pay in est tax payments and just send in enough to cover what I think I’ll owe. Been loose with it and Never got hit with any penalties.
**The math:**
To definitely avoid a penalty regardless of how much you earn in 2026, you need to pay 110% of your 2025 tax.
110% of $68869 is $75,756
Assuming you withhold $66990 again, you will be short $8766
Divide by 4 (and round up)
**Discussion:**
This is calculated by your filing software, not the IRS.
You will owe a late-payment penalty if you don’t pay the lesser of:
* 90% of the tax you actually calculate was due in 2026 when you file in 2027.
* this $75,756 calculated from your 2025 tax
through some combination of withholding and equal quarterly payments.
If your income is highly variable, you might not be able to predict that first number when making your quarterly payments. But if all your income is from a salary that stays consistent from year to year, don’t worry about the 110%. Just increase your withholding to cover what you actually owe.