Tax Planning
You Missed a Quarterly Tax Payment. Now What?
This is not a crisis and it is not nothing. The penalty behaves like interest on the amount you were short, for the time you were short — which means the useful response is speed, not worry.
01What the penalty actually is
It is not a flat fine. It is computed on how much you underpaid and for how long, which is why a payment made three weeks late costs far less than the same shortfall carried to April. The practical consequence: pay as soon as you notice, even if you cannot pay the full amount. Partial and immediate beats complete and later.
02Do not skip the next one to compensate
The instinct is to treat the year as already lost. It is not — the calculation runs period by period. Missing the next payment as well compounds a manageable problem into a worse one. Pay what you can now, and pay the next one on schedule.
03Route one: the safe harbour may already cover you
Before assuming you owe a penalty, check whether you have already paid at least 100% of last year's tax through a combination of estimated payments and withholding — or 90% of this year's. Either generally avoids the penalty. People who front-loaded payments or have W-2 withholding alongside a business are sometimes covered without realising it.
04Route two: annualise, if your income is lumpy
The default calculation assumes you earned evenly across the year. If you did not — a seasonal business, one large project in the autumn, a slow start — you can annualise your income and compute unequal required payments, which often reduces or eliminates the penalty. This is done on Form 2210, and it is the most commonly missed remedy in this whole area.
05The W-2 lever, one more time
If you or a spouse have wage income, increasing withholding for the rest of the year is generally treated as if it had been paid evenly all year. That is a genuine repair mechanism for an underpayment already incurred, and there is no equivalent for estimated payments. If it is available to you, it is usually the first thing to try.
06Then fix the cause
Almost every missed payment I see traces back to the same thing: the money was never separated, so by the due date it had been spent on something legitimate. A dedicated account and a fixed transfer on every deposit prevents the next four.
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Schedule a ConsultationThis article is general information, not individualized tax, legal, or financial advice. Every situation is different — reach out and we'll look at yours directly.