Forgot to Pay Estimated Taxes by Due Date

Ooops, I forgot to pay my state estimated tax due date of June 15, and paid it today on June 27.  Even though I expect to pay over 100% of our estimated taxes, there my still be a small interest payment due for being late based on the rules of estimated payments.

Here's my understanding of the rules:

• Estimated payments need to be paid by the due date to be considered on time without verification.  Withholding payments can be paid at anytime without consideration for timing.
• If estimated payments are not paid on time, there are two ways to be exempted from interest payments:
• Estimated payment were made later due to timing of receiving income, which is not received regularly.
• The amount owed is less that the threshhold for interest to be charged.
• Otherwise, a form to calculate the interest penalty should be filled out or one can allow the tax agency to compute the interest penalty.
• Finally, one can ask for penalty forgiveness to be granted this one time.

I don't expect to pay interest penalty for this missed payment.   First, my quarterly payments are greater than our expected tax liability divided by 4.  Second, our income is lumpy and skewed towards the end of the year, with 20% of income coming in December.

Anyway, I'm lucky this year.  I will put in place a process to avoid late estimated payments in 2027.  Specifically, I will over pay on the first quarter which should offset any late payments in the remaining quarters.

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This is not financial nor tax advice. Please consult a professional advisor.

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