How to Invoice a Client: A Step-by-Step Guide for Your First Bill

To invoice a client, agree the price and payment terms in writing before you start, then send a clear invoice as a PDF by email when the work is done — with all the required details, a due date, and instructions for how to pay. After that, follow up politely if the payment date passes. That short loop — agree, send, follow up — is the whole job, and getting it right the first time sets the tone for every payment that follows.

This guide walks through the full client workflow: how to agree terms up front, when to send the invoice, exactly what to say when you deliver it, and how to chase a late payment without damaging the relationship. If you instead want help building the document itself — the layout, the line items, the numbering — see our walkthrough on how to create an invoice and the field-by-field checklist in what to include on an invoice. Here, the focus is on the client.

Step 1: Agree the price and terms before you start

The most common cause of an awkward, unpaid invoice is a conversation that never happened. Before any work begins, you and the client should both understand and have in writing what is being done, what it costs, and when payment is due. This does not need to be a formal contract — a confirming email or accepted quote is usually enough — but it must exist somewhere you can point back to.

At a minimum, settle these points before you begin:

• Scope: exactly what you will deliver, so "done" is not a matter of opinion later.
• Price: a fixed total, an hourly or day rate, or a clear estimate with a cap.
• Payment terms: when payment is due — for example on receipt, or within 14 or 30 days of the invoice date.
• Deposit: for larger or first-time jobs, whether you require an upfront payment before work starts.
• How they will pay: bank transfer, card, or another method you actually accept.

Payment terms are worth deciding deliberately rather than defaulting to whatever the client suggests. Net 30 is common for established business clients, but shorter terms get you paid faster and are perfectly normal for a small operator or a new relationship. Our guide to invoice payment terms explains the common options and how to phrase them so there is no ambiguity about the due date.

A client who agrees to your price and terms in writing has already agreed to pay the invoice. The invoice is just the paperwork that follows a decision they have already made.

If you are an individual billing a larger company, ask early whether they need a purchase order (PO) number, vendor onboarding form, or a specific email or portal for invoices. Big organisations often will not pay an invoice that lacks a PO number, no matter how correct it is — and finding that out after you send it costs you weeks.

Step 2: Decide when to send the invoice

Timing matters more than most people expect. The faster an invoice reaches the client after the work, the faster it tends to get paid — partly because the value you delivered is still fresh, and partly because a prompt invoice signals that you run an organised business that expects to be paid on time.

How you time it depends on the type of work:

• One-off projects: invoice immediately on completion, the same day if you can. Do not let it slip to "the end of the month" out of habit.
• Larger projects: consider a deposit before you start and a balance on delivery, or staged payments tied to milestones, so you are never carrying the full cost of the work.
• Ongoing or retainer work: invoice on a fixed, predictable schedule — for example the first of each month — so the client knows exactly when to expect your bill.

For first-time clients especially, an upfront deposit protects you. You are extending credit to someone whose payment habits you do not yet know, and a deposit both reduces your risk and confirms the client is serious before you invest your time.

Step 3: Create the invoice with everything the client needs

A client pays an invoice faster when there is nothing on it to question and nothing missing that they have to ask about. Every invoice should clearly carry your details, the client's details, a unique invoice number, the date, an itemised list of what you are charging for, the total (including any tax), the due date, and your payment instructions.

Rather than repeat the full anatomy here, build it once and reuse it: our step-by-step on how to create an invoice shows the process from blank page to finished PDF, and the required-fields checklist makes sure nothing is left off. You can put a complete, professional invoice together in a couple of minutes with our free online invoice generator — no sign-up, and it exports straight to PDF.

A few client-facing details are worth getting exactly right the first time:

• The client's legal name and address — use the registered business name they invoice under, not a casual brand name, especially if they reclaim tax.
• A unique, sequential invoice number — this is how both of you reference the bill in every later email.
• A clear description of the work — specific enough that a finance person who never spoke to you can approve it.
• A PO number, if they gave you one — place it prominently; its absence can stall payment in large companies.

Always send the finished invoice as a PDF, not an editable document. A PDF looks the same on every device, prints cleanly, and cannot be accidentally altered — which is exactly what a client's accounts team expects to receive and file.

Step 4: Send the invoice and say the right thing

For most freelancers and small businesses, the standard way to deliver an invoice is as a PDF attached to a short email. It lands directly with your contact, creates a timestamped record, and is easy for them to forward to whoever actually approves payments. Some larger clients will instead ask you to upload invoices to a supplier portal — if so, follow their process, but still send a brief heads-up email so a real person knows it is there.

The covering message should be short and friendly. You are not negotiating; you are confirming a payment that was already agreed. A good message does four things: thanks the client, confirms the work, states the amount and due date, and points to how to pay.

A worked example

Say you are a freelance designer named Alex. You finished a logo for a client, Brightway Cafe, for an agreed £600, on terms of payment within 14 days, paid by bank transfer. Your email might read:

Subject: Invoice 0007 — Brightway Cafe logo

Hi Sam, thanks again for the chance to work on the new Brightway logo — I hope you're happy with how it turned out. I've attached invoice 0007 for the agreed £600. It's due by 7 July, and my bank details for transfer are on the invoice. Any questions, just let me know — and thanks! Alex

That is the whole template: warm, specific, and impossible to misread. Notice that the amount, the due date, and the payment method all appear in the message itself, not only on the attachment — busy clients skim the email before they open the PDF. For more wording you can adapt, including first-invoice and reminder versions, see our collection of templates in the guide on how to send an invoice by email.

If you are an individual invoicing a company, the email is identical in spirit; you simply invoice under your own name (and tax number, if you have one) rather than a registered company name. The client treats you as a supplier either way. The same guide on sending invoices by email covers the small adjustments that help an individual's invoice clear a company's accounts process smoothly.

Step 5: Track it and confirm it arrived

Once an invoice is out, it is easy to assume it will simply get paid — and then forget about it until you wonder, weeks later, why you have not been paid. Avoid that by keeping a simple record of every invoice you send: the client, the invoice number, the amount, the date sent, the due date, and whether it has been paid. A spreadsheet is perfectly adequate when you are starting out.

It is also reasonable to send a brief acknowledgement nudge a day or two after delivery if you hear nothing at all — a one-line "just checking invoice 0007 reached you okay" — particularly with a new client. Silence usually means a busy inbox, not a refusal, but a gentle confirmation makes sure your invoice has not been lost before the clock even starts.

Step 6: Follow up professionally when payment is late

Even with good clients, invoices slip past their due date. Following up is a normal, expected part of running a business — not an accusation — and the clients who pay late most often are simply the ones who are never reminded. Keep your tone calm and assume good faith, especially in the first reminder.

A reliable follow-up ladder looks like this:

1. A day or two after the due date: a friendly reminder assuming it was an oversight. Re-attach the invoice and restate the amount and how to pay.
2. About a week later: a slightly firmer note referencing your agreed terms and asking for a specific payment date.
3. Two to three weeks overdue: a clear, still-professional message stating that the invoice is now significantly overdue and what happens next, such as a late-payment fee if your terms allow one.

If your original terms mentioned a late fee or interest, you can apply it at this stage — but late-fee rules and the interest you may legally charge vary by country and even by state or region, so set yours in line with local norms and keep it modest. The point of a follow-up is to get paid and keep the relationship, not to win an argument. Most overdue invoices are resolved by the first or second reminder.

The single most effective collection tactic is also the simplest: actually following up. A polite reminder on a fixed schedule recovers the large majority of late invoices with no friction at all.

Keep good records after you are paid

When an invoice is paid, mark it as such in your tracker and keep a copy of the invoice and the payment confirmation. You will need these for your own bookkeeping and tax return. As a general rule, businesses keep invoices and supporting records for several years — commonly in the range of around five to seven years — but the exact retention period is set by your local tax authority and varies by country, so confirm the requirement for where you operate.

Doing this consistently turns invoicing from a recurring scramble into a routine. Each new client follows the same loop you have now established: agree terms, send promptly, follow up if needed, file the record. Once that habit is in place, billing your second client — and your fiftieth — takes only a few minutes.

Frequently Asked Questions

How do I invoice a client for the first time?

Agree the price and payment terms in writing first, then create the invoice with all the required fields, send it as a PDF by email with a short covering message, and set yourself a reminder to follow up if it is not paid by the due date. Doing those four things — agree, build, send, follow up — in order is all the first invoice requires.

How do I send an invoice to a client?

The most common and professional way is to attach the invoice as a PDF to a short, polite email. Keep the message brief, confirm the amount and due date, and explain how to pay. See our guide on how to send an invoice by email for templates and tips. Some larger clients use a supplier portal instead, in which case you upload the invoice there and send a short heads-up email as well.

When should I invoice a client?

For one-off work, invoice immediately when the work is finished, or take a deposit before you start. For ongoing or retainer work, invoice on a set schedule such as monthly. Invoicing promptly is one of the biggest factors in getting paid on time, so deciding your payment terms up front and sending without delay both matter.

What do I say when sending an invoice?

Keep it brief and friendly: thank the client, confirm the work you completed, state the total amount and the due date, and tell them how to pay. A short, clear message reads as professional and makes it easy for the client to act. You can adapt ready-made wording from our email templates guide for the first invoice and for reminders.