How to Invoice Clients (and Actually Get Paid on Time)

A practical, no-fluff guide to sending invoices that look professional, leave no room for confusion, and get money into your account faster.

Invoicing The Billable Team · · 7 min read
A person signing a document at a desk

For a lot of solo business owners, invoicing is the part of the job nobody warned you about. You did the work, you did it well, and now you’re staring at a blank document wondering what a “proper” invoice is even supposed to look like. Get it wrong and you end up chasing payment for weeks. Get it right and the money shows up quietly, on time, without you having to think about it.

Here’s how to get it right.

What every invoice needs

An invoice is a legal request for payment, not a friendly note. It should leave zero ambiguity about who owes what, for what, and by when. At a minimum, include:

  • Your business name and contact details — and the client’s too.
  • A unique invoice number. Sequential is easiest (INV-001, INV-002). You’ll need this for your records and taxes.
  • The issue date and a clear due date. “Due on receipt” is vague; “Due by 14 September 2025” is not.
  • An itemised list of work with a short description, quantity or hours, rate, and line total.
  • The total amount due, with any tax broken out separately.
  • Payment instructions — bank details, a payment link, whatever you accept.

That last one matters more than people think. Every extra step between “I want to pay this” and “it’s paid” is a chance for the invoice to get buried.

Set payment terms before you start

The best time to agree on how you’ll be paid is before you’ve done a single hour of work. Put your terms in the proposal or contract: your rate, when invoices go out, the payment window (Net 7, Net 14, Net 30), and what happens if payment is late.

Shorter terms are almost always better for a solo business. Net 30 is a corporate default that made sense when invoices moved by post. You are not a corporation with a treasury department. Net 7 or Net 14 keeps your cash flow healthy and signals that you take payment seriously.

Send it immediately

The single biggest lever on how fast you get paid is how fast you invoice. An invoice sent the day you finish is far more likely to be paid promptly than one that lands three weeks later, when the client has mentally moved on and the budget has been reallocated.

Build invoicing into the end of every project or the same day each month. Don’t let it pile up into a dreaded quarterly admin session.

Make the numbers impossible to argue with

Disputes and delays usually trace back to a client not understanding a charge. Head this off by being specific. Instead of “Design work — $2,000,” write “Homepage redesign (3 concepts + 2 revision rounds) — $2,000.” When the line item matches what you actually agreed to deliver, there’s nothing to question.

Follow up like it’s normal, because it is

Late payments happen to everyone. A polite, matter-of-fact reminder a day or two after the due date is completely professional — it is not nagging. Most late invoices are simply forgotten, not refused. A calm nudge usually solves it.

Where Billable comes in

Everything above is straightforward — and also exactly the kind of thing that quietly eats your evenings when you’re doing it by hand in a word processor and a spreadsheet. That’s the problem Billable was built to remove.

You create a clean, professional invoice in a couple of clicks — numbering, dates and totals handled for you. Your clients and their history live in one place, so you’re never re-typing details. And when an invoice slips past its due date, Billable sends a polite reminder for you, automatically, so you get paid faster without the awkward follow-up. It’s invoicing and finances for solopreneurs, for a flat $9 a month. If chasing payments is stealing your focus, give it a try.

Run the money side of your solo business.

Billable helps solopreneurs create invoices, manage clients and projects, and stay on top of their finances — all in one calm place. One plan, $9/mo, everything included.