Who pays quarterly
Anyone expecting to owe roughly $1,000+ for the year beyond withholding: freelancers, LLC owners, S-corp shareholders with distribution income, landlords, investors with big gains.
Safe harbors — how to never owe a penalty
- Pay 90% of this year's tax as you go, or
- Pay 100% of last year's tax (110% if prior-year AGI topped $150K)
Hit either harbor across the four dates and the underpayment penalty disappears, whatever April brings.
The dates
April 15, June 15, September 15, January 15 — note the uneven gaps; Q2 is only two months long, which is where most people fall behind.
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