How to Send an Invoice (And Actually Get Paid on Time)

Sending an invoice isn't just emailing a PDF. Timing, format, payment terms, and follow-up cadence all determine whether you get paid in 15 days or chase payments for 90. Here's the complete system.

Most freelancers and agencies treat invoicing as an afterthought. Finish the work, attach a PDF, fire off an email, hope the money shows up. It usually does — eventually. The average freelancer waits 30–45 days to get paid. For agencies, it's 45–60 days. That's not a client problem. It's a process problem. The difference between getting paid in 15 days and chasing a payment for 60 days almost never comes down to whether the client is "good" or "bad." It comes down to how you invoice: what you include, when you send it, what terms you set, and what happens when the due date passes without payment. This guide covers the complete system — from what goes on the invoice to what to do when someone doesn't pay.

Step 1: What Every Invoice Must Include

An invoice that's missing information creates friction. The client's accounts payable team can't process it, so it sits in someone's inbox until they get around to asking you for the missing details. That delay is entirely preventable.

Every invoice you send should include:

• Your business name, address, and contact information. If you're a sole proprietor, use your business name (or your legal name if you don't have one). Include email and phone.
• Client's company name and billing contact. Get this right — "Acme Inc." is not the same as "Acme Corp" in many AP systems. Ask for the exact legal name and billing address during onboarding.
• Unique invoice number. Use a sequential system: INV-001, INV-002, INV-003. Never reuse a number. This makes reconciliation and tax filing straightforward.
• Invoice date and due date. The invoice date is when you issue it. The due date is when payment is expected. Don't write "Net 30" and make them do math — write the actual calendar date.
• Line items with descriptions. Each item should include a description of the work, quantity or hours, rate, and the line total. "Website development — 40 hrs @ $150/hr = $6,000" is clear. "Development work — $6,000" is not.
• Subtotal, tax (if applicable), and total. If you charge sales tax or VAT, break it out separately. The total should be unmistakable.
• Payment instructions. Bank transfer details, PayPal address, or a Stripe payment link. Make it as easy as possible for them to pay. If they have to email you asking "where do I send the money," you've already lost days.
• Late payment terms. State them on every invoice: "1.5% monthly interest applies to balances overdue by more than 30 days." You rarely need to enforce it — the clause itself motivates on-time payment.

Need a starting point? Download the freelance invoice template or the consulting invoice template for a ready-to-use format that covers all of these fields.

Step 2: When to Send the Invoice

Timing is the single biggest lever you control. Every day you delay sending an invoice is a day added to your payment timeline. If you finish a project on Tuesday and send the invoice the following Monday, you've already added five days of float — before the client's payment cycle even starts.

Milestone billing: Send the invoice the same day the milestone is delivered. Not the next day. Not at the end of the week. The day. Tie it to the deliverable so the work is fresh in the client's mind and there's no ambiguity about what they're paying for.

Monthly retainers: Send on the 1st of the month for prepaid retainers. For retainers billed in arrears, send on the last day of the month. Consistency matters — if your client's AP team knows your invoice arrives on the 1st, it gets slotted into their payment cycle automatically.

Hourly billing: Invoice weekly or biweekly. Waiting until the end of the month to send a single large invoice increases the odds of sticker shock, disputes, and delayed approval. Smaller, more frequent invoices get processed faster and keep your cash flow steady.

The cardinal rule: The longer you wait to invoice, the longer you wait to get paid. Your delay becomes their delay. If you're billing Net 15 but sending the invoice a week late, you've effectively given yourself Net 22 — and that gap compounds over every billing cycle.

Step 3: Payment Terms That Actually Work

Payment terms aren't just bureaucratic fine print. They're the rules of engagement for when and how you get paid. Set them clearly at the start of the relationship and include them on every invoice.

Net 15 over Net 30. Most clients pay relative to the due date, not the invoice date. If you set Net 30 and they pay on day 28, that's fine — but if you'd set Net 15, they would have paid on day 14. Shorter terms don't offend clients. They just move the goalpost closer.

Early payment discount. Offer "2% discount if paid within 10 days" — written as 2/10 Net 30 in accounting shorthand. This works surprisingly well with larger companies where AP teams are incentivized to capture discounts. On a $10,000 invoice, a 2% discount ($200) to get paid 20 days faster is almost always worth it.

Late payment fee. State it on every invoice: "1.5% monthly interest on balances overdue by more than 30 days." Most clients will never trigger it. But the presence of the clause changes behavior — it signals that you track payment timing and take it seriously.

Upfront deposits. Require 25–50% upfront for new clients or projects over a certain threshold. This is non-negotiable for first engagements. A client who refuses to pay a deposit before work begins is a client who's likely to be difficult to collect from after work is complete. The deposit also aligns incentives: you're not carrying all the financial risk while the client carries none.

Step 4: The Invoice Email

The email you attach the invoice to matters more than most people think. A vague subject line gets buried. A wall of text gets skimmed. A missing payment link means the client has to open the PDF, find your bank details, and manually set up a transfer — each step adding friction and delay.

Here's what works:

Subject: Invoice #[number] — [Project Name] — Due [date]

Hi [Name],

Please find attached Invoice #[number] for [brief description of work completed].

Amount due: $[total]
Due date: [date]
Payment: [bank transfer / Stripe link / PayPal]

Let me know if you have any questions.

Best,
[Your name]

Three principles: keep it short, include the amount and due date in the email body (not just inside the PDF), and make payment easy with a direct link. If you use Stripe or PayPal, include a clickable payment link in the email. The fewer steps between "I should pay this" and "I paid this," the faster you get your money.

Don't bury the invoice in a long project update email. Send it separately with a clear subject line that includes the invoice number, project name, and due date. AP teams process dozens of invoices a week — make yours easy to find and act on.

Step 5: The Follow-Up System

Sending the invoice is step one. Following up is how you actually get paid. Most people either don't follow up at all (and wonder why payments are late) or follow up erratically (one angry email after 45 days). Neither works. What works is a predictable cadence:

3 days before due date: A friendly heads-up. "Just a reminder that Invoice #X for $Y is due on [date]. Here's the payment link: [link]. Let me know if you need anything." This is not aggressive — it's helpful. It gives AP teams time to queue the payment.

On the due date: A brief, direct note. "Invoice #X is due today. Amount: $Y. Payment link: [link]. Thanks!" No need to be apologetic. The payment is due. You're confirming it.

7 days past due: More direct. "Invoice #X for $Y was due on [date] and is now 7 days overdue. Could you let me know when I can expect payment? If there's an issue with the invoice, I'm happy to resolve it."

14 days past due: Formal. "This is a second notice regarding Invoice #X, now 14 days past due. Per our agreement, a late fee of 1.5% monthly will apply to balances overdue by more than 30 days. Please process payment at your earliest convenience."

30+ days past due: Final notice before escalation. State clearly that you will pause all active work on the client's projects until the outstanding balance is resolved. Follow through.

Here's a template for the 7-day overdue reminder:

Subject: Payment reminder — Invoice #[number] (7 days overdue)

Hi [Name],

Invoice #[number] for $[amount] was due on [date] and is now 7 days past due.

Could you let me know when I can expect payment? If there's an issue with the invoice, I'm happy to resolve it.

Payment link: [link]

Thanks,
[Your name]

The key is consistency. Send every reminder on schedule regardless of how you feel about it. Automating this process removes the emotional friction entirely — you don't have to decide whether it's "too soon" or "too pushy." The system handles it.

Step 6: When They Don't Pay

Sometimes, despite clear terms and systematic follow-up, a client doesn't pay. Here's the escalation path:

Pause work. After 30 days overdue, stop all active work on that client's projects. Send written notice: "Due to the outstanding balance of $X on Invoice #Y, all work on [project] is paused effective immediately. Work will resume once payment is received." This is not a threat — it's a boundary. You are not a bank, and continuing to deliver work while carrying unpaid invoices is unsustainable.

Offer a payment plan. Some clients genuinely have cash flow issues. They intend to pay but can't do it all at once. For these situations, offer a structured payment plan: split the balance into 2–3 installments over 30–60 days. Get the agreement in writing. This works when the issue is ability, not willingness.

Collections. This is the last resort. For amounts under $10,000, small claims court is often the most practical path — filing fees are low and you don't need a lawyer. For larger amounts, a collections agency can pursue the debt on your behalf, typically taking 25–50% of recovered funds. Factor the cost and effort into your decision: sometimes writing off a small invoice and firing the client is the better business decision.

Prevention beats collection. The best strategy for non-payment is never reaching this point. Upfront deposits filter out clients who can't or won't pay. Milestone billing limits your exposure on any single deliverable. Clear terms set expectations from day one. Systematic follow-up catches problems early. If you do all four consistently, you'll eliminate 90% of payment issues before they start.

The Invoice Checklist

Before you hit send on any invoice, run through this:

• Unique invoice number assigned
• Correct client billing name and address
• Accurate line items with clear descriptions
• Explicit due date (a calendar date, not just "Net 30")
• Payment instructions with a clickable link
• Late payment terms stated on the invoice
• Sent the same day as delivery (not days or weeks later)

If all seven boxes are checked, your invoice is ready. If any are missing, fix it before sending — every gap is an opportunity for delay.

Stop Chasing Payments

The system described above works. But running it manually — tracking due dates, drafting reminder emails, checking which invoices are overdue — takes time that could be spent on billable work. Corcava generates invoices automatically from tracked time, sends them on your billing schedule, and follows up when payments are overdue. Your time data, invoicing, and follow-up live in one system, so nothing falls through the cracks. See how invoicing fits into the full profitability lifecycle →