No employer is withholding taxes from your income anymore, which means it's on you to send the IRS money four times a year, not once.
When you're an employee, your employer withholds income tax and payroll tax from every paycheck automatically. As a freelancer, nobody's doing that for you, so the IRS expects you to estimate your tax bill and pay it in four installments throughout the year instead of one lump sum in April. Skip it, and you can owe a penalty on top of the tax itself, even if you pay everything in full by the filing deadline.
Both are based on net profit, revenue minus business expenses, which is exactly why tracking expenses accurately matters so much: every dollar of legitimate expense lowers both taxes at once.
For a typical calendar-year filer in the US, estimated payments are due roughly:
Dates shift a few days when they land on a weekend or federal holiday, always double-check the exact date on irs.gov for the current year.
The Ledgerline tax estimate calculator takes your expected income, expenses, and tax rate and breaks it into four suggested quarterly payments with due dates.
Estimate my taxes →The freelancers who dread this the least keep a running tally of income and expenses all year, not a scramble the week before each deadline. Track expenses as they happen, revisit your estimate each quarter, and set aside the money in a separate account the moment you get paid so it's never a surprise.