How to send an invoice and get paid on time | Xero

Published Monday 30 March 2026

Table of contents

• Before you send an invoice
• What to include in your invoice
• When to send an invoice
• How to send your invoice
• How to write an invoice email
• Best practices for getting paid faster
• What to do when invoices go unpaid
• Simplify invoicing with Xero
• FAQs on sending invoices

Key takeaways

• Establish clear payment terms and expectations before starting any work to prevent confusion and speed up payment, as 82% of business failures stem from poor cash flow management.
• Include all essential invoice details such as your business information, customer details, unique invoice number, due date, itemised services, and clear payment instructions to ensure professional compliance and faster processing.
• Send invoices immediately after completing work and use email with PDF attachments for the fastest delivery, while offering multiple payment options like bank transfer, card payments, and online links to make it easy for customers to pay.
• Follow up proactively with friendly reminders before due dates and contact customers promptly when payments are late, as waiting longer makes collection more difficult and affects your cash flow.

Before you send an invoice

Discussing payment expectations upfront prevents confusion and speeds up payment later. This is critical given a U.S. Bank study found that 82% of business failures stem from poor cash flow management tied to payment terms.

Agree on payment terms before you send your first invoice. Discuss when you'll bill (weekly, monthly, or on completion) and how long they'll have to pay.

Clear expectations prevent surprises. Your customer should know exactly when they'll need to pay before you begin any work.

What to include in your invoice

Your invoice needs specific information to be complete, professional, and legally compliant. Missing details can delay payment or cause confusion.

Required invoice details

Include the following:

• Your business details: name, address, and contact information
• Customer details: name, company, and billing address
• Invoice number: a unique reference for tracking
• Invoice date: when you created the invoice
• Due date: when payment is expected
• Itemised list: description of goods or services with quantities and prices
• Total amount: including any applicable taxes
• Payment instructions: how and where to pay

Optional information that helps you get paid faster

Adding these details can speed up payment:

• Purchase order number: if your customer provided one
• Project or job reference: helps larger organisations match invoices to budgets
• Early payment discount: an incentive for paying before the due date
• Late payment terms: what happens if payment is overdue
• Your logo and branding: looks professional and builds trust

For a ready-to-use format, try an invoice template. You can also read our guide on how to make an invoice for more detail.

When to send an invoice

Timing your invoices correctly keeps cash flowing and sets clear payment expectations.

When you send an invoice affects how quickly you get paid. The right timing depends on the type of work you do.

Invoice immediately after completion

Send your invoice as soon as the job is done or the order is filled. The sooner you bill, the sooner you get paid. For one-off jobs or small projects, invoice on the same day if possible.

Set up recurring invoices for regular work

If you're on a retainer or selling subscriptions, send invoices at consistent intervals. Monthly billing works well for ongoing services. Consider using invoicing software to send these automatically so you never miss a billing cycle.

Use milestone billing for large projects

For bigger projects, send interim invoices as you complete each phase. This keeps cash flowing throughout the project rather than waiting until the end. Milestone billing also reduces your risk if the client relationship changes.

Think about your cash flow when setting your billing schedule, as research from Sievo indicates that strategic payment terms can unlock 5–10% of working capital. Spreading invoices throughout the month creates steadier income than billing everything at once.

How to send your invoice

You have three main options for delivering invoices. Each has different advantages depending on your business and your customer's preferences.

Send your invoice by email

Email is the fastest and most common method. Your invoice arrives instantly, creates a clear record, and is easy for customers to forward to their accounts team.

To send invoices by email effectively:

1. Use a PDF format so the invoice can't be edited
2. Include a clear subject line with the invoice number
3. Double-check the recipient's email address
4. Follow up with a quick call after your first invoice to confirm receipt

Use online invoicing software

Online invoicing platforms let you create, send, and track invoices in one place. You send your customer a secure link, and they can pay immediately by card or bank transfer.

Online invoicing offers these benefits:

• Faster payments: customers can pay with one click
• Automatic tracking: see when invoices are viewed and paid
• Built-in reminders: set up automatic follow-ups for overdue invoices
• Reduced fraud risk: secure links are harder to intercept than email attachments

Mail a paper invoice (when it makes sense)

Some customers still prefer posted invoices, particularly larger organisations with formal accounts payable processes. If you need to mail an invoice:

1. Confirm the correct postal address and contact name
2. Allow extra time for delivery and processing
3. Keep a copy for your records
4. Consider following up by email to confirm receipt

How to write an invoice email

The email you send with your invoice matters as much as the invoice itself. A clear, professional message helps your invoice get processed quickly.

Write a clear subject line

Your subject line determines whether your invoice gets opened or ignored. Include the invoice number and your company name so it's easy to find and file.

Here are some effective subject line examples:

• Invoice #1234 from [Your Company] – Due [Date]
• [Your Company] Invoice #1234 for [Project Name]
• Payment request: Invoice #1234 – [Amount]

Ask your customer's accounts team if they have a preferred format. Some require a purchase order number in the subject line.

Keep your message simple and professional

You don't need a lengthy email. A brief, friendly message works best:

"Hi [Name],

Please find attached invoice #1234 for [brief description]. The total is [amount] and payment is due by [date].

Let me know if you have any questions.

Thanks for your business."

Include all payment details

Make sure your email includes these key details so customers can act quickly:

• Invoice number: for easy reference
• Amount due: the total they need to pay
• Due date: when you expect payment
• Payment methods: how they can pay you

The invoice itself contains the full breakdown, but highlighting key details in your email makes it easier for customers to act quickly.

Best practices for getting paid faster

Small changes to your invoicing process can significantly speed up payment times. These practices help you get paid sooner and reduce the time spent chasing overdue invoices.

Offer multiple payment options

Make it easy for customers to pay you. The more payment methods you accept, the fewer excuses customers have for delays.

Consider offering these payment methods:

• Bank transfer
• Credit or debit card
• Online payment links
• Direct debit for recurring invoices

Make payment instructions crystal clear

Confusion causes delays. Include your bank details, payment reference, and accepted methods directly on the invoice. Don't make customers search for how to pay you.

Send invoices in secure, uneditable formats

PDF invoices are harder to tamper with than Word documents or spreadsheets. Fraudsters have been known to intercept emailed invoices and change the payment details. A PDF or online invoice link reduces this risk.

Follow up proactively, not reactively

Don't wait until an invoice is overdue to check in. A friendly reminder the day before the due date shows you're organised and sets expectations. Customers are more likely to prioritise invoices from businesses that clearly track their payments.

What to do when invoices go unpaid

Many invoices go past their due date. In the U.S., 60% of small businesses report cash flow issues that stem directly from late payments or extended terms. Here's how to handle late payments professionally and effectively.

Send a friendly reminder before the due date

A quick reminder the day before payment is due can prevent delays. Keep it brief and helpful:

"Hi [Name],

Just a reminder that invoice #1234 is due tomorrow. Let me know if you need anything to process it.

Thanks"

This shows you're organised and sets the expectation that you track your invoices closely.

Follow up promptly when payment is late

Act quickly once an invoice is overdue. The longer you wait, the harder it becomes to collect. Send a polite but direct message:

"Hi [Name],

Invoice #1234 was due on [date] but I haven't received payment yet. Please let me know when I can expect it, or if there's an issue I can help resolve.

Thanks"

Make the phone call when emails don't work

If emails go unanswered, a phone call often gets results. It feels awkward, but that's exactly why it works: it's uncomfortable for them too.

Keep the call simple:

1. State which invoice is overdue
2. Ask when you can expect payment
3. Let them do the talking
4. Don't fill silences; wait for their response

Automate your payment reminders

For many businesses, chasing invoices takes too much time. Online invoicing software can send automatic reminders when invoices are due or overdue.

The software tracks your invoices and watches for matching payments. When an invoice remains unpaid, it sends a pre-written reminder on your behalf. You only need to get involved when reminders are ignored.

Simplify invoicing with Xero

Sending invoices shouldn't take time away from running your business. Xero handles the details, from creating professional invoices to tracking payments and sending automatic reminders, so you can focus on what matters.

With Xero, you can:

• Create and send invoices in minutes from any device
• Track payment status and see what's outstanding at a glance
• Set up automatic reminders for overdue invoices
• Accept online payments so customers can pay instantly

Ready to make invoicing easier? Get one month free and see how Xero can help you get paid faster.

For more on handling late payments, read our guide on chasing outstanding invoices.

FAQs on sending invoices

Here are answers to common questions about sending invoices.

Can I send an invoice by email, or does it need to be posted?

Yes, you can send invoices by email. Email is the most common method and is generally faster and more reliable than post. Send your invoice as a PDF attachment or use online invoicing software to share a secure payment link.

What should I do if I sent an invoice to the wrong email address?

Contact the recipient immediately and ask them to delete the invoice without opening it. Then send the invoice to the correct address and update your records to prevent future errors.

How long should I keep copies of sent invoices?

Keep copies of all invoices for at least five years. This helps with tax compliance, but other rules may require longer periods; for example, the Sarbanes-Oxley Act requires auditors to retain audit workpapers and supporting invoices for seven years. Keeping good records also helps with resolving disputes and tracking your business finances. Storing digital copies in accounting software makes this easier to manage.

Can I send an invoice before completing the work?

Yes, in some situations. You can request a deposit or advance payment before starting work, or send interim invoices for completed milestones on larger projects. Make sure you agree on payment terms with the customer beforehand.

What's the difference between an invoice and a receipt?

An invoice requests payment for goods or services and you send it before receiving payment. A receipt confirms that the customer has paid and you issue it after completing the transaction.