Generally, most taxpayers will avoid this underpayment penalty if they either owe less than $1,000 in tax after subtracting their withholding and refundable credits, or if they paid withholding and estimated tax of at least 90% of the tax for the current year or 100% of the tax shown on the return for the prior year, whichever is smaller. For next year you can either pay quarterly estimated tax payments or have your withholding increased by an amount that you will own from the consulting business.
