Outstanding invoices: how to get paid and prevent late payments

Published Monday 18 May 2026

Table of contents

• What is an outstanding invoice?
• Outstanding vs overdue invoices: what's the difference?
• How do unpaid invoices affect your business?
• How to chase late payments
• Invoice tracking and payment management
• When you still don't receive payment
• Tips for avoiding late payments
• Streamline your invoicing with Xero
• FAQs on outstanding invoices
• Disclaimer

Key takeaways

• Outstanding invoices are bills you've sent but haven't been paid yet. They become overdue only after the payment due date passes, so it's worth tracking both types separately.
• Late payments hurt your cash flow and your ability to pay your own bills. The longer an invoice stays unpaid, the harder it becomes to collect, so act early.
• A structured follow-up process gets results. Start with friendly reminders before the due date and escalate gradually through formal demands, using email templates at each stage.
• Tracking and automation prevent invoices from slipping through the cracks. Use accounts receivable aging reports and automated reminders to stay on top of what's owed.

What is an outstanding invoice?

An outstanding invoice is a bill you've sent to a customer that hasn't been paid yet. It covers any invoice that's still open, whether the due date has passed or not.

When you deliver a product or complete a service, you send an invoice requesting payment within a set timeframe. Until your customer pays that invoice, it's considered outstanding. This is a normal part of doing business, especially if you offer payment terms like net 15 or net 30.

Outstanding invoices show up as accounts receivable on your books. They represent money you've earned but haven't collected. Keeping a close eye on these invoices helps you understand how much cash you're actually expecting to come in, and when.

The key thing to know is that "outstanding" doesn't automatically mean "late." An invoice can be outstanding and still within its payment window. It only becomes a problem when it crosses into overdue territory.

Outstanding vs overdue invoices: what's the difference?

The difference between an outstanding invoice and an overdue invoice comes down to timing. An outstanding invoice is any unpaid bill, while an overdue invoice is one that's past its due date.

Think of it this way: all overdue invoices are outstanding, but not all outstanding invoices are overdue. If you send an invoice on May 1 with net 30 terms, it's outstanding from the moment you send it. It only becomes overdue on May 31 if it hasn't been paid.

This distinction matters for how you communicate with clients. You'll want a different tone for a friendly reminder about an upcoming payment than you would for a formal notice about a bill that's 30 days late. It also affects your bookkeeping, since overdue invoices may need provisions for bad debt or trigger late payment fees depending on your terms.

Understanding the difference between an outstanding invoice vs an unpaid invoice helps you prioritize your follow-up efforts. Focus your energy on the overdue invoices first, while keeping tabs on everything that's still outstanding.

How do unpaid invoices affect your business?

Unpaid invoices disrupt your cash flow and can put your entire operation at risk. When customers don't pay on time, you may struggle to cover your own expenses, from rent and payroll to supplier payments.

Here's how late payments create a ripple effect across your business:

• Cash flow gaps: You've already done the work or delivered the product, but the money isn't in your account. This gap between earning and receiving makes it harder to plan and invest.
• Wasted time on collections: Every hour spent chasing payments is an hour you're not spending on growing your business. For small business owners, this time cost adds up fast.
• Strained client relationships: Following up on overdue invoices can feel awkward, but letting them slide can breed resentment and set a precedent for late payment.
• Increased borrowing costs: If unpaid invoices force you to take on a line of credit or short-term loan to cover expenses, you're paying interest on money that should already be yours.
• Tax complications: Depending on whether you use cash accounting or accrual accounting, unpaid invoices can affect how you report income and manage your tax obligations.

The longer an invoice goes unpaid, the less likely you are to collect it. Industry data suggests that after 90 days, the chances of collecting drop significantly. That's why acting early and having a clear process matters.

How to chase late payments

Chasing late payments works best when you follow a structured process that starts friendly and escalates gradually. The goal is to get paid while keeping your client relationships intact.

Here are eight steps to follow when an invoice goes unpaid, including ready-to-use email templates you can customize for your situation.

1. Send a friendly reminder before the due date

Don't wait for an invoice to become overdue. A polite reminder a few days before the due date keeps payment top of mind for your client and shows professionalism.

Subject: Friendly reminder: Invoice [#number] due on [date]

Hi [client name],

I hope you're doing well. This is a quick reminder that invoice [#number] for [amount] is due on [date]. I've attached a copy for your reference.

If you've already sent payment, please disregard this message. Otherwise, please let me know if you have any questions.

Thanks, [Your name]

This approach works especially well for new clients or larger invoices where you want to make sure nothing falls through the cracks.

2. Send a payment request on the due date

If the due date arrives and you haven't received payment, send a direct but courteous request. Keep the tone neutral and assume the best, since it may simply be an oversight.

Subject: Payment due today: Invoice [#number]

Hi [client name],

I wanted to let you know that invoice [#number] for [amount] is due today, [date]. I've attached the invoice for your convenience.

Could you confirm that payment is on its way, or let me know if there's anything you need from my end to process it?

Best regards, [Your name]

3. Send an overdue notice at seven days past due

At this point, the invoice is officially overdue. Your tone should remain professional but more direct. Reference your payment terms and any late fees outlined in your original agreement.

Subject: Overdue: Invoice [#number], seven days past due

Hi [client name],

I'm following up on invoice [#number] for [amount], which was due on [date]. As of today, it's seven days past due.

Per the payment terms outlined in the original agreement, I'd appreciate prompt attention to this matter. Please let me know if there's an issue with the invoice or if you need to arrange a different payment timeline.

Thank you, [Your name]

4. Send a formal demand at 30 days past due

After 30 days, it's time for a more formal approach. This email should clearly state the consequences of continued non-payment, whether that's late fees, suspension of services, or further action.

Subject: Formal notice: Invoice [#number], 30 days past due

Dear [client name],

This is a formal notice regarding invoice [#number] for [amount], originally due on [date]. Despite previous reminders, this invoice remains unpaid at 30 days past due.

Please arrange payment within seven business days. If payment is not received by [specific date], I may need to [suspend services/apply late fees/refer the matter for further action] as outlined in the terms of the agreement.

If there are circumstances preventing payment, I'm open to discussing a payment plan. Please reach out at your earliest convenience.

Regards, [Your name]

5. Send a statement of accounts

If your client has multiple outstanding invoices, send a statement of accounts that lists everything they owe in one place. This gives them a clear picture of the total balance and makes it easier to reconcile payments.

A statement of accounts is especially useful for ongoing client relationships where invoices stack up monthly. It removes ambiguity and gives both sides a single reference point.

6. Follow up with a phone call

Sometimes an email isn't enough. A brief phone call can resolve issues faster and uncover reasons for the delay, such as a lost invoice, internal approval bottlenecks, or cash flow problems on the client's side.

Keep the conversation professional. Ask if there's anything preventing payment and whether you can help resolve it. If the client is facing financial difficulty, this is a good time to discuss a payment plan.

7. Apply late payment fees

If your contract or invoice payment terms include late payment fees, apply them after your grace period expires. Let the client know the fee has been added and include the updated total in your next communication.

Late fees serve two purposes: they compensate you for the time value of the delayed payment, and they motivate faster payment in the future. Make sure any fees you charge comply with your state's regulations.

8. Escalate further if needed

If you've exhausted your own collection efforts, you have a few options:

• Cut off future work: Stop providing services or products until the outstanding balance is settled. This protects you from accumulating more unpaid invoices.
• Hire a debt collection agency: A third-party collector can take over the recovery process. They typically charge a percentage of the amount collected.
• Consult a lawyer: For significant amounts, legal action may be worth the investment. A lawyer can send a demand letter, which often prompts payment, or pursue the debt through small claims court.

Each escalation step carries trade-offs, so weigh the cost of recovery against the amount owed and the importance of the client relationship.

Invoice tracking and payment management

Tracking your outstanding invoices in a structured way helps you spot problems early and prioritize your collection efforts. A solid accounts receivable process is the backbone of healthy cash flow. Rather than reacting to overdue invoices one at a time, a system-level approach keeps you in control.

Accounts receivable aging reports

An accounts receivable aging report groups your outstanding invoices by how long they've been unpaid. It typically breaks invoices into buckets: current, 1 to 30 days overdue, 31 to 60 days, 61 to 90 days, and over 90 days.

To set one up, start by listing every unpaid invoice along with the client name, amount, invoice date, and due date. Then sort them into the aging buckets based on how many days past due they are. You can build this in a spreadsheet or use accounting software that generates the report automatically.

Review your aging report weekly. It shows you at a glance where your biggest risks are and which clients need immediate follow-up.

How to prioritize which invoices to chase first

Not every outstanding invoice deserves the same level of urgency. Prioritize based on a combination of factors:

• Amount owed: Larger invoices have a bigger impact on your cash flow, so they deserve attention first.
• Age of the invoice: The older an invoice gets, the harder it is to collect. Focus on invoices that are about to cross into the next aging bucket.
• Client relationship: A long-term client who's a few days late is different from a new client who's 30 days overdue. Adjust your approach accordingly.
• Payment history: If a client has a pattern of paying late, you may want to follow up sooner than you would with a typically reliable payer.

Key metrics to monitor

Tracking a few numbers gives you a clear picture of how well your collections process is working:

• Days sales outstanding (DSO): This measures the average number of days it takes to collect payment after a sale. A lower DSO means you're collecting faster.
• Collection rate: The percentage of invoices you successfully collect within a given period. Aim to keep this as high as possible.
• Aging buckets distribution: Monitor what percentage of your receivables fall into each aging bucket. If the 60-plus-day bucket is growing, your follow-up process needs attention.

Tracking invoices across multiple clients

If you're a freelancer or consultant working with several clients at once, invoice tracking becomes even more important. Keep a single, centralized record of all your invoices rather than managing them client by client.

Use a consistent invoicing process: number your invoices sequentially, set clear payment terms upfront, and log every invoice as soon as you send it. A centralized system, whether that's a spreadsheet or accounting software, makes it easy to see your total outstanding balance and spot any invoices that need follow-up.

When you still don't receive payment

Sometimes, despite your best efforts, a client simply doesn't pay. When you've exhausted your follow-up process, you have a few remaining options to consider.

Writing off bad debt

If an invoice is genuinely uncollectable, you may need to write it off as bad debt. This removes the amount from your accounts receivable and records it as a loss. In many cases, you can deduct bad debt from your taxes, though the rules depend on your accounting method.

The IRS provides guidance on deducting bad debts, including the documentation you'll need to support your claim. Your accounting software should let you record the write-off as a bad debt expense.

Before writing off a debt, make sure you've documented every attempt to collect, including emails, phone calls, and any written agreements. This documentation protects you if the deduction is ever questioned.

Checking credit before extending terms

One of the best ways to avoid uncollectable invoices in the future is to check a potential client's creditworthiness before offering payment terms. A business credit score gives you a snapshot of how reliably a company pays its bills.

For larger contracts or new clients, consider running a credit check or asking for trade references. You can also protect yourself by requiring a deposit upfront or setting shorter payment terms until the client establishes a track record of on-time payment.

Reporting to a disputes register

If a client refuses to pay despite clear documentation of the debt, you can report the unpaid invoice to a disputes register. This creates a public record of the dispute and can motivate the client to settle, since it may affect their own creditworthiness.

This step is typically a last resort, but it can be effective when other approaches have failed.

Tips for avoiding late payments

Preventing late payments starts with setting clear expectations before you ever send an invoice. A proactive approach to reducing payment delays saves you time and protects your cash flow. A few upfront steps can significantly reduce the number of overdue invoices you deal with.

Set clear payment terms from the start

Include your payment terms on every invoice and in your contracts. Specify the due date, accepted payment methods, and any late fees that apply. The clearer you are upfront, the less room there is for confusion later.

Consider offering shorter payment terms like net 15 instead of net 30 to speed up collection. You can learn more about structuring your terms in this guide to invoice payment terms.

Make it easy to pay

The fewer obstacles between your client and the "pay" button, the faster you'll get paid. Offer multiple payment methods, such as bank transfer, credit card, and online payment links. Send invoices electronically using e-invoicing software so clients can pay with a single click.

Use a professional invoice template that clearly shows the amount due, due date, and how to pay. A clean, well-formatted invoice reduces the chance of it getting lost or ignored.

Offer early payment incentives

A small discount for early payment, such as 2% off if paid within 10 days, can motivate clients to pay ahead of schedule. This approach costs you a little on each invoice but can dramatically improve your overall cash flow.

Invoice promptly

Send your invoice as soon as the work is complete or the product is delivered. The longer you wait to invoice, the longer you wait to get paid. Prompt invoicing also signals professionalism and keeps the transaction fresh in your client's mind.

Use invoice automation tools

Automating your invoice reminders and follow-ups removes the manual effort of chasing payments and ensures no invoice slips through the cracks. Here's what to look for in an invoice automation tool:

• Automatic payment reminders: The tool should send scheduled reminders before, on, and after the due date without you needing to do anything.
• Payment tracking: You should be able to see at a glance which invoices have been paid, which are outstanding, and which are overdue.
• Aging reports: Built-in accounts receivable aging reports help you monitor your overall collections health.
• Recurring invoices: If you bill the same clients regularly, the ability to set up automatic recurring invoices saves time.

Compared to manually tracking invoices in a spreadsheet and sending follow-up emails one by one, automation handles the routine work so you can focus on running your business. It also creates a consistent follow-up cadence, which means clients always receive timely reminders regardless of how busy your week gets.

Streamline your invoicing with Xero

Managing outstanding invoices doesn't have to eat into your time. Xero's online invoicing software helps you create professional invoices, send automatic payment reminders, and track what's been paid, all from one place.

With Xero, you can:

• Send invoices from anywhere: Create and send invoices on the go from your phone, tablet, or computer.
• Automate payment reminders: Set up automatic reminders so clients get notified before, on, and after the due date, without you lifting a finger.
• Accept online payments: Let clients pay directly from the invoice with credit card or bank transfer, reducing the time between sending and receiving payment.
• Track outstanding invoices in real time: See your accounts receivable at a glance with built-in dashboards and aging reports.
• Connect your favorite apps: Extend Xero's functionality with over 1,000 apps in the Xero App Store.

Whether you're a freelancer tracking invoices across multiple clients or a growing business managing a high volume of transactions, Xero's invoicing features adapt to your needs.

Get one month free

FAQs on outstanding invoices

Here are answers to some common questions about managing outstanding invoices.

What is the meaning of an outstanding invoice?

An outstanding invoice is a bill that has been sent to a customer but hasn't been paid yet. It includes any invoice that's still open, whether it's within the payment window or past due. Outstanding invoices appear as accounts receivable in your financial records.

How long should you wait before following up on an unpaid invoice?

Don't wait for an invoice to become overdue before reaching out. Send a friendly reminder a few days before the due date, then follow up on the due date itself. If payment is still missing after seven days, send a formal overdue notice and escalate from there.

How do you write an effective email about an outstanding invoice?

Keep the email short, professional, and specific. Include the invoice number, amount owed, original due date, and a clear request for payment. Attach a copy of the invoice for easy reference. Adjust your tone based on how far past due the invoice is, starting friendly and becoming more formal over time.

What is the best way to track outstanding invoices?

The most reliable method is to use an accounts receivable aging report that groups unpaid invoices by how long they've been outstanding. Review this report weekly to spot issues early. Accounting software can generate these reports automatically, but you can also build a simple version in a spreadsheet.

Can you write off an unpaid invoice on your taxes?

In many cases, yes. If you've made reasonable efforts to collect and the debt is genuinely uncollectable, you may be able to deduct it as bad debt. The IRS has specific rules about documentation and eligibility, so check IRS Topic 453 on bad debt deductions or consult a tax professional.