Invoicing

You're profitable on paper and broke in your checking account.

That's Net-30. The work is done, the invoice is out, and rent is due before the money lands. Figure out how big a cushion bridges the gap.

Cash-flow math, not accounting theory
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Tax data last updated: July 2026. Sources & methodology

Your cash cycle

$

What you invoice in a typical month.

days

Net-30 means the clock starts when you send the invoice, not when you did the work.

days

Be honest. 'Net-30' often means 42 in practice.

$

What actually leaves your account each month.

Cash buffer you need
$7,700

Money you invoice today lands in about 42 days — this buffer covers the gap.

Real wait per invoice
42 days
Receivables always in transit
$11,200
Buffer to never miss a bill
$7,700

Rough model assuming steady billing. Two levers shrink the buffer fast: a deposit up front (30–50% is normal) and shorter terms — Net-15 with new clients is easier to set than to negotiate later. Late fees help too, once they're in the contract.

How this is calculated

We take your real wait per invoice — the stated terms plus the days clients habitually run late — and compute two numbers. First, the receivables always in transit: money you've earned that hasn't arrived, roughly your daily billing times the wait. Second, the one that matters: enough cash to cover your actual monthly costs across that same wait.

That second figure is your working-capital floor. Below it, one slow-paying client means choosing which bill to skip. On top of it, most freelancers keep a separate 3–6 month emergency fund — the buffer handles timing, the fund handles losing a client entirely.

Formula
Buffer = (monthly costs ÷ 30) × (terms + average days late)

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Common questions

Corporate accounts-payable departments batch payments on a schedule, and 30 days became the default decades ago. It's a convention, not a law — plenty of freelancers quote Net-15, or 50% upfront, and clients mostly just... agree.
Deposits. Collecting 40% before work starts means nearly half your revenue skips the waiting line entirely. After that: shorter terms for new clients, invoicing the moment work ships instead of month-end, and a late-fee clause for the stragglers.
Price it in or push back. Sixty days of float is a loan you're making them interest-free — big companies ask precisely because freelancers don't charge for it. A fair response: Net-60 at a 5% higher rate, or Net-30 as quoted. Watch how fast Net-30 becomes fine.
Last resort. Factoring services advance you the invoice minus 2–5%, which annualizes to painful rates. A deposit habit and a built-up buffer solve the same problem for free — factoring makes sense mainly for one-off cash crunches, not as a system.