Last Updated April 28, 2025
Invoices are a fundamental part of doing business, but what happens when you spot a mistake after sending one out? Whether it’s a typo, missing information, or a billing error, knowing how to fix an error on an invoice you’ve already sent is a crucial skill for maintaining your credibility and keeping your records accurate.
In this guide, you’ll learn how to revise an invoice properly. Plus, we’ll cover how to spot mistakes early and how you should revise both paid and unpaid invoices.
What Is a Revised Invoice?
Businesses sometimes need to send revised invoices to their customers to correct errors in the original invoice. Whether it’s due to a pricing mistake, incorrect client information, or missing details like an invoice number, businesses sometimes need to revise an invoice to ensure accuracy and compliance.
A revised invoice replaces the original and needs to have a label on it that says “revised,” so it’s clear which invoice the client should pay. This formal record acknowledges and corrects a mistake in an earlier invoice.
Errors can happen even if you follow business accounting best practices, but revisions allow you to maintain accurate records. In some cases, especially when dealing with larger transactions, errors could have legal implications under incorrect invoice laws. That’s why it’s crucial to promptly issue a revised invoice with all the correct information.
What Happens if an Invoice Is Incorrect?
Invoice mistakes not only cause confusion, but if left unaddressed, they can delay payments, harm client trust, and even lead to legal action. If an invoice is incorrect, you need to amend it and issue a revised invoice to fix the error and avoid bigger problems down the line.
For minor typos, it may be enough to send a revised invoice promptly and notify the client. However, if you spot pricing or service discrepancies, you might also need to issue a credit note for an incorrect invoice to formally adjust the balance. From a legal perspective, incorrect invoice laws differ by jurisdiction, but in most cases, you’re required to correct invoice errors. If the error is bad enough (or you wait too long to issue a correction), you may be required to cover the costs.
Addressing an incorrect invoice quickly and professionally—whether with a polite incorrect invoice email or a formal incorrect invoice letter—helps maintain strong customer relationships and avoids unnecessary payment disputes.
Invoice revisions don’t have to be stressful or hurt your business. Errors and misunderstandings will happen, and that’s why every small business needs internal controls to catch mistakes before sending invoices to clients. For example, invoice automation tools can prevent most invoicing mistakes, while invoice verification ensures clients receive accurate billing.
How to Revise an Unpaid Invoice
If you’ve discovered an error on an unpaid invoice, don’t panic. There’s a straightforward process you can follow to revise an invoice quickly.
1. Create a Revised Invoice
The first step is to generate a revised invoice with the corrections. Proper invoice reconciliation ensures all charges and details are accurate. Always reference the original invoice number and label the document appropriately so that your customer knows it’s a revised or amended invoice.
2. Alert Your Accounting Team
After revising the invoice, notify your internal accounting or accounts receivable team. Whether your business uses software for business accounting or tracks payments manually, accounting will need to update your company records based on the correct invoice. Updating internal records ensures that reports and tax documents are as accurate and up-to-date as possible.
3. Email the Revised Invoice to Your Debtor
The last step is to send a revised invoice to the customer. Make sure to explain the corrections and attach the revised invoice or amended invoice. But don’t just send the invoice without an explanation. Be professional, clear, and polite in your communication, and explain how the error happened. If it’s a bigger error, like a pricing discrepancy, explain the steps you’ll take to prevent it from happening again. As always, thank the customer for their business and make yourself available to answer any questions.
If you promised the customer you would change your processes, make sure you do just that. Take steps to prevent this from happening again. For example, learning how to write an invoice properly (and verify its charges) can minimize the chances of needing corrections later.
How to Revise a Paid Invoice
Correcting an invoice that’s already been paid can be a little trickier, but it’s doable with the right approach.
1. Address the Payment by Deleting the Recording
First, you’ll need to delete or void the payment record associated with the incorrect invoice in your accounting system. This step is crucial because you can’t modify a closed invoice in most accounting software without first reversing the recorded payment. If you’re using accounting software, the process should be relatively straightforward. Always double-check your system’s guidelines for handling payment reversals.
2. Make a Revision Note in Your Accounting Software
Once you remove the payment, make a note in the software explaining why you’re modifying the invoice. Good documentation is key, especially when it comes to invoice amendments. This can also simplify compliance if you need to refer back to this information during an audit.
3. Create Your Revised Invoice
Now, it’s time to create a revised invoice. Just like with unpaid invoices, you’ll want to label it appropriately by referencing the original invoice number. As always, double-check the details to ensure that this invoice is correct. Sending multiple revised invoices can harm customer trust, so ensure you get the revision right the first time.
4. Alert Your Accounting Team
Notify your accounting team so they can update their internal records. They may need to update tax records or financial reports based on the revised invoice, depending on the magnitude of the changes.
5. Email the Revised Invoice to Your Debtor With an Explanation
Once everything is ready on your side, it’s time to notify the client. This process is more challenging because the client already paid. It requires even more care and communication, especially if you charged late fees or increased the invoice total. Depending on the severity of the change, you may need to schedule a call with the client to explain what happened. Have a copy of your contract or written scope of work on hand in case they have questions.
6. Re-record the Payment
When the customer acknowledges and pays the new invoice, record the payment again in your accounting software, this time matching it to the corrected invoice. Keeping your books clean at every step will make your business accounting far easier and prevent issues during audits or reporting.
Tips for Writing an Email for a Revised Invoice
Whether you do it manually or through accounting software, you likely send invoices to customers via email. Email is great for leaving a paper trail, but you need to pay careful attention to your choice of words when communicating about invoice revisions. How you handle revised invoices will have a tremendous impact on customer relationships. Follow these tips to write the perfect revised invoice email:
- Act fast: As soon as you notice the issue, act quickly. Whether you’re dealing with a minor typo or a significant billing error, it’s essential to address the mistake promptly before it causes payment delays or confusion. Let your client know you’re issuing a revised or amended invoice and explain why.
- Use a template: It can feel awkward admitting to a mistake, but it’s essential for running your business profitably and with integrity. If you aren’t sure what to say, use an email template to politely ask for payment.
- Watch your tone: Mistakes happen, and most customers are understanding as long as you communicate with courtesy. Whether you’re sending a quick incorrect invoice email or a more formal revised invoice letter, being polite can help maintain strong working relationships. Tools like Grammarly can analyze your tone and make suggestions to help you sound professional and friendly over email.
- Provide relevant information: Always include the original invoice number in your message to avoid any confusion. Clearly label the new document as either a revised invoice or an amended invoice and double-check all details before sending. Making sure everything is accurate this time can save you from having to issue another correction later.
- Apologize if necessary: If the error caused an inconvenience to the client (like unexpectedly increasing the cost of an invoice), a brief apology goes a long way. However, after apologizing, you should emphasize the steps you’ve taken to prevent problems in the future and that you sincerely appreciate the customer’s business. A good client will understand that mistakes happen, and vowing to do better in the future will help you regain their trust.
In-Summary: Revising Invoices
Invoice mistakes happen. From simple typos to major billing errors, knowing how to revise an invoice can save your business money and hassle while preserving client goodwill. Still, you should follow the proper procedures—not only to stay legally compliant but also to keep your internal accounting records clean and accurate. Follow the tips in this guide to ensure clean books, speed up payment timelines, and preserve customer trust.
Revising Invoices FAQs
Can an invoice be revised?
Absolutely. If you notice an error, you can and should revise an invoice to correct it. Businesses often issue a revised invoice to fix mistakes such as incorrect pricing, wrong client details, or missing elements like an invoice number. Not only is this a legal requirement, but invoice amendments also keep your accounting records clean and help you maintain good customer relationships.
Do I have to pay for an incorrect invoice?
If you receive an incorrect invoice, you shouldn’t pay it until the error is corrected. Always communicate with the sender to clarify and request a revised invoice or, if necessary, a credit note for the incorrect invoice.
Is it legal to amend an invoice?
Yes, it’s legal to amend an invoice as long as the changes are properly documented and communicated. In fact, processing an incorrect invoice could put your business in legal trouble, so you must amend it if you catch an error.
Michael McCareins is the Content Marketing Associate at altLINE, where he is dedicated to creating and managing optimal content for readers. Following a brief career in media relations, Michael has discovered a passion for content marketing through developing unique, informative content to help audiences better understand ideas and topics such as invoice factoring and A/R financing.
