The 15.3% on every editing invoice
When you edit as a freelancer, no employer is withholding Social Security and Medicare from your pay. The IRS still wants those contributions, so it collects them through self-employment tax: 12.4% for Social Security plus 2.9% for Medicare, a combined 15.3%. An employee splits that bill with an employer. A freelance editor pays both halves.
The 15.3% applies to your net profit, not your gross deposits. If clients paid you $70,000 this year and you spent $12,000 on editing software, plugins, stock footage, and a workstation, self-employment tax is calculated on the $58,000 that is left (technically on 92.35% of it, a built-in adjustment on the form). Every legitimate write-off you track lowers this tax directly, which is why editors who log expenses all year keep meaningfully more of their per-video pay.
Self-employment tax is also separate from income tax. You owe both. Income tax depends on your bracket, filing status, and deductions; self-employment tax is a flat 15.3% layer underneath it.
Schedule C, Schedule SE, and the $400 floor
Your editing income and expenses go on Schedule C, which produces your net profit. That number flows to Schedule SE, the form that actually computes self-employment tax, and both attach to your Form 1040.
The threshold is low: once net earnings from self-employment reach $400 for the year, you must file and pay. That is true even if a client never sent you a 1099-NEC, even if you were paid through PayPal or Venmo, and even if editing is a side gig next to a day job. Your own records are what determine the number, not the forms clients remember to send.
One ceiling worth knowing: the 12.4% Social Security piece only applies up to an annual wage base that adjusts each year, so very high earners stop paying that portion at some point. The 2.9% Medicare piece has no cap. Check the current-year wage base rather than assuming last year's figure.
Half of it comes back, and estimates keep you penalty-free
Two pieces of good news. First, you deduct the employer-equivalent half of your self-employment tax on Schedule 1 of Form 1040, which lowers your income tax. Second, the whole system is predictable, so you can plan for it.
Because nothing is withheld from editing payments, the IRS expects you to prepay through quarterly estimated taxes using Form 1040-ES, due roughly April 15, June 15, September 15, and January 15. A simple habit covers it: move a fixed percentage of every client payment into a separate tax account the day it lands, then draw the quarterly payments from there. Editors who wait until April to think about the 15.3% are the ones who get surprised; editors who skim it off each invoice barely notice it.