
Quarterly Estimated Taxes for the Self-Employed in 2026: Safe Harbors, Form 1040-ES, and the Annualized Income Method
A working guide to the 2026 quarterly estimated tax rules for freelancers and self-employed earners — the two IRS safe harbors (90% current year, 100%/110% prior year), the four uneven due dates, Form 1040-ES, the annualized income method for lumpy earners, EFTPS vs Direct Pay, and the mistakes that trigger penalties at the 6–7% federal rate.










