Set Aside 30% for Taxes — But 30% of What?

Every new drone business owner hears the same advice: "set aside 30% for taxes." Nobody ever finishes the sentence. Thirty percent of what? The check the client wrote? What's left after gas and software? Something else entirely?

It matters more than it sounds. Get the base wrong in one direction and you hand the IRS an interest-free loan you could have used for a second battery. Get it wrong in the other direction and you're writing a check in April you don't have.

So let's finish the sentence. This is not tax advice — I'm a pilot, not a CPA, and your situation has wrinkles mine doesn't. This is the plain-English version of the vocabulary, so the conversation with your preparer takes ten minutes instead of an hour.

Three numbers that are not the same thing

Say you flew a $500 mapping job. You drove 100 miles round trip.

Gross revenue: $500. Every dollar that landed in your account. This is the number on the invoice, and it is the number most people accidentally multiply by 30%.

Net profit: $500. For the sake of a clean example, say the job cost you nothing out of pocket. This is your cash result.

Taxable net: about $428. Net profit minus the deductions that never cost you cash. The big one for drone operators is mileage: 100 miles at the 2026 standard rate of $0.725 a mile is a $72.50 deduction — even though you only burned about $15 in actual gas. The IRS hands you that $57.50 difference for free. You take the mileage deduction instead of saving gas receipts, never both.

The 30% comes off taxable net. Not gross. Not cash net. Taxable net — the Schedule C bottom line.

Run it: 30% of $428 is about $128. Thirty percent of the $500 gross would have been $150. On one job that's a $22 difference. Across sixty jobs a year it's the price of a drone.

Why 30% at all

The "30%" rule of thumb is two taxes stacked:

• Self-employment tax — 15.3%. Social Security (12.4%) plus Medicare (2.9%). This is the one that blindsides people who come from a W-2 job, where the employer quietly paid half. Working for yourself, you pay both halves. It's assessed on 92.35% of your net earnings, not 100% (IRS, Self-Employment Tax).
• Federal income tax — whatever your bracket works out to. For most side-hustle operators stacking drone income on top of a day job, the effective rate lands somewhere in the 10–22% range. Note: effective, not marginal. Your marginal rate is what the next dollar gets taxed at; your effective rate is the average across all of it, and it's always lower.

Add 15.3% to a 12% effective rate and you're at 27.3%. Round up, call it 30%, and you have a cushion. That's the whole origin of the rule. It's not magic and it's not a law — it's arithmetic with a safety margin.

If you're in a state with income tax, add that on top. Colorado's flat 4.4% doesn't sound like much until you forget it for three quarters.

The side-hustle wrinkle nobody mentions

If you have a W-2 day job, your employer is already withholding. That withholding can absorb some or all of the income tax on your drone income — but it does nothing for self-employment tax. That 15.3% is yours alone.

Two workable approaches, both legitimate:

1. Pay quarterly estimates on the drone income (the standard route).
2. Bump your W-2 withholding by filing a new Form W-4 with your employer, so the day job covers the whole family of taxes. Withholding is treated as paid evenly across the year no matter when it happened, which is why this trick can rescue somebody who's already behind (IRS, Estimated Taxes).

Full-timers don't get option two. Quarterlies are the job.

The dates, and why Q2 and Q3 are weird

Federal estimated tax payments are due four times a year, and the "quarters" are not quarters:

• Q1 — covers Jan–Mar, due April 15
• Q2 — covers Apr–May (two months), due June 15
• Q3 — covers Jun–Aug (three months), due September 15
• Q4 — covers Sep–Dec (four months), due January 15 of the following year

Yes, Q2 is two months long and Q4 is four. No, nobody can explain why. Just put them in your phone.

Miss one and the penalty isn't a fine so much as interest on the money you were supposed to have sent. There's a safe harbor: generally you're clear of the underpayment penalty if you pay at least 90% of this year's tax, or 100% of last year's total tax (110% if your prior-year income was over $150,000) (IRS, Estimated Taxes). For a first-year business, last year's number is often tiny — which makes the 100%-of-last-year route the easy, cheap way to stay safe.

Mileage is a shield, not an expense

This one trips up everybody, so it gets its own heading.

IRS standard mileage rate (2026): $0.725/mi (72.5¢ per mile) for business use of a personal vehicle. Multiply your business miles by this rate to get your deductible vehicle expense — no separate fuel, maintenance, or depreciation receipts required when you use the standard rate. Verify the current year's rate at IRS — Standard Mileage Rates before filing. Rotor Rate auto-updates this rate every January as the IRS publishes its annual notice.

The standard mileage rate is not money you spend. It's money you don't get taxed on. Your gas and wear are real cash leaving the bank; the deduction is the government agreeing not to tax an equivalent slice of your revenue.

Practical effect: at a combined ~27% rate, every deductible mile puts about 19 cents back in your pocket at filing time. A 340-mile week is roughly $65 of tax you don't owe. That's not profit, it's a discount on your tax bill — but it's real, and it's the single most-missed deduction among part-time operators because nobody writes the trips down.

The catch is the IRS expects a contemporaneous log — records made at or near the time of the trip, not reconstructed from memory in March. Rotor Rate logs the miles with the mission for exactly this reason. Related reading: what mileage actually does to your tax bill .

A worked quarter

Let's do a real-ish Q3 for a part-timer:

• Six missions, $4,100 collected
• $310 out of pocket — gas beyond the mileage rate, a lens filter, a month of processing software, parking
• 620 miles logged, at $0.725 a mile = $450 of deduction

Net profit: $4,100 − $310 = $3,790 in the bank. Taxable net: $3,790 − $450 = $3,340.

• Self-employment tax: $3,340 × 92.35% × 15.3% = $472
• Federal income tax at a 12% effective rate: $401
• Colorado at 4.4%: $147

Set-aside: $1,020, of which $873 goes to the IRS on September 15 and $147 goes to the state.

Thirty percent of taxable net would have said $1,002. Close enough that the rule of thumb works — which is the point. The rule is fine. The base is what people get wrong.

What Rotor Rate does with this

The app already knows your missions, your miles, your out-of-pocket costs, and your rate settings, so it does the arithmetic above every time you mark a job complete. The quarterly widget on your saved jobs shows the current quarter's set-aside; the Business Dashboard shows all four quarters side by side.

New this week: a pre-filled Form 1040-ES payment worksheet. Hit the button on any quarter and you get a one-page PDF with your name, your address, the quarter, the due date, and the exact federal amount — plus the line-by-line math showing where the number came from, so you or your preparer can check it in about fifteen seconds. There's a link straight to IRS Direct Pay if you'd rather pay online, and a four-page packet you can hand your accountant at year end alongside the rest of the tax package.

Two deliberate design choices. The worksheet leaves your Social Security number blank for you to write in by hand — we don't store it and never will. And the amount on it is federal only, because Form 1040-ES is a federal form; your state estimated payment goes to your state on its own form, and the worksheet reminds you of the amount without pretending otherwise.

The short version

• Set aside 30% of taxable net — Schedule C bottom line, after both cash expenses and mileage.
• The 30% is roughly 15.3% self-employment plus your effective income rate. Add your state on top.
• Pay quarterly: April 15, June 15, September 15, January 15.
• Mileage is a tax shield, not an expense. Log it the day you drive it.
• Bank the set-aside in a separate account. Money sitting in your operating account eventually looks like money you can spend, because it is.

And then go talk to a real preparer. The cheapest hour you'll buy all year is the one where somebody who does this for a living looks at your Schedule C and says "you missed this."

Sources & further reading

• IRS — Estimated Taxes — due dates, safe harbor rules, who has to pay.
• IRS — Self-Employment Tax (Social Security and Medicare Taxes) — the 15.3% and the 92.35% base.
• IRS — About Form 1040-ES — the official voucher and worksheet.
• IRS — Standard Mileage Rates — the current-year business rate.
• IRS — About Schedule C — where net profit actually gets reported.