How to Keep Your Business's Invoicing and Billing Data Secure

According to UK Finance, most payment frauds don’t come from some high-tech hacking; instead, it comes from things we don’t think we need to look at carefully. For example, an invoice that looked close to real. Moreover, in 2025, businesses and individuals have been victims of exactly these traps and have lost over £1.28 billion in a year alone.

And that’s the scary part, especially if you run a small business, because now it does not take long hacking skills for someone to commit payment fraud; all it takes is one tired evening and an email that looks almost real. 

It’s Not Carelessness, It’s Multi-Tasking 

Unlike big corporations, most small business owners don’t have the time of day when they are able to check invoices on big monitor screens with nothing else having their attention. Usually, with a variety of tasks at hand, small business owners tend to group multiple tasks together to save time and get as many things done as possible. This basically means that unlike top-shot CEOs, these business owners review an invoice while picking up their kids from school or while making dinner at home.  Their laptop usually lies on a kitchen table with a dozen other unfinished things. Fraud knows this. It’s built for exactly that moment.

And that’s why most people never even realise that they have been a victim of fraud until it already happens. And this does not happen because of their carelessness; this only happens because checking the invoice properly would have meant stopping what felt like a routine task to treat it as a suspicious one. And with almost every other invoice sent by suppliers looking like this one, there is no reason to do that. 

Most people don’t make that switch mid-task. That’s not a character flaw. It’s just how attention works when you’re running a household and a business at the same time.

The National Cyber Security Centre calls this business payment fraud, and its own guidance is straightforward about the mechanism: someone impersonates a supplier or a colleague, asks for a payment or a change to bank details, and counts on the request looking ordinary enough that it sails through.

Three Things to Check Before Signing an Invoice 

There are usually only a few common things to notice regarding an invoice which almost every time tells you exactly what you need to know. 

The Bank Details Have Moved

This is the one that is the most obvious yet is the most overlooked. See, a supplier whose invoiced you about five times would not usefully change the account on the sixth invoice without a warning. So if an account number or code is different from all the previous times that you made the payment, it is worth double-checking. 

The Urgency Feels Manufactured

Urgency is usually the first sign of any kind of fraud. This is because the attackers know that if they give you too much time, you might actually check the authenticity of the document and they will get caught. In order to avoid that, they try to trap you within a time frame so you do not have enough time to figure it out.

Genuine suppliers hardly ever need a same-day payment on a first-time exchange because they understand how the business works. But if an email urges you to make the payment almost instantly by using terms like “process before end of the day” or “our accounts team needs this now,” it’s a good chance that it might be a fraud.  

The Address Is Almost Right

A single swapped letter in a domain name is easy to miss at 8 pm. It’s the small tell that survives every other check, because nobody expects to need reading glasses to catch a crime.

Before paying anything that fails even one of these checks:

1. Call the supplier on a number you already had before the email arrived — never one printed on the invoice itself.
2. Pull up the last invoice you paid them and compare the account details side by side.
3. Wait. A legitimate request survives a 24-hour delay. A scam usually doesn’t.

Where a Home-Run Business Gets This Wrong

The reason why this fraud happens with most small businesses is that things like these do not get checked twice by someone else, essentially because at the beginning of a small business there is no one else. And attackers know this well. That’s why instead of having the whole invoice system living inside just one person’s inbox and being just one person’s headache, an alternative has to be established. 

And fixing this does not necessarily mean hiring someone and spending more money than what the business is making. It just means writing the check down somewhere, a note or a shared doc, anything that isn’t memory, so that “did we verify this?” is a real step, not a thing you assume you’d have noticed.

Keep the Paperwork Boring, on Purpose

Patterns and consistency are usually what help a small business be protected from frauds like this. Setting up a system where every invoice follows the same format is helpful because the one that is not like the rest of them makes it easier for you and your vendor/supplier to spot it. 

Businesses building their own invoices from a fixed, repeatable format — Luzenta.com offers a free Google Docs invoice template built this way — tend to notice the fakes faster, simply because there’s a known shape to compare against. Nothing fancy. Just something that doesn’t change every time.

If a Payment Has Already Gone Out

Although if a payment has already gone out, do not waste your time getting embarrassed or questioning how you actually fell for such tricks. 

There is usually a short window before any payment clears, so always call your bank after a fraudulent payment is made from your account.  You can also report it through Action Fraud, or gov.uk/report-cyber for a live incident, which reaches the National Cyber Security Centre’s response team directly. 

Moreover, telling every other supplier mentioned in that email thread also helps avoid instances of such fraud. Don’t lose time to panic first. Every business owner who’s dealt with this has a version of the same story.

Frequently Asked Questions

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