How to send an invoice: step by step to get paid faster

Published Monday 20 April 2026

Table of contents

• Before you send an invoice
• What to include in your invoice
• How to invoice
• Ways to send an invoice
• How to write an invoice email
• When to send an invoice
• Track your invoices and payments
• Overdue payment reminder email (or call)
• The gentle reminder email you don't have to write
• Send invoices with confidence
• FAQs on sending invoices

Key takeaways

• Establish clear payment terms, billing schedules, and accepted payment methods with customers before sending your first invoice to prevent delays and disputes.
• Include all essential details in every invoice: a unique invoice number, your business and customer contact information, a clear description of goods or services, itemised costs with any applicable taxes, and straightforward payment instructions.
• Send invoices as soon as work is complete rather than batching them together, as invoicing promptly keeps your cash flow steady and gets you paid faster.
• Use invoicing software to track outstanding payments in real time and send automatic reminders when invoices become overdue, so you spend less time chasing payments manually.

Key takeaways

• Establish clear payment expectations upfront. Discuss billing schedules, payment terms, and accepted payment methods with customers before sending invoices to prevent delays and disputes.

• Include all essential invoice elements: unique invoice numbers, business and customer contact details, descriptions of goods or services, itemised costs with taxes, and clear payment instructions.

• Send invoices immediately when work is complete rather than batching them monthly. Use email with PDF attachments or online invoicing software for fast, secure delivery.

• Use automated invoice tracking and payment reminders to monitor outstanding invoices in real time. These systems send polite follow-up messages automatically when payments become overdue.

Before you send an invoice

Setting clear expectations with customers before your first invoice prevents payment delays and disputes.

Discuss these key points before you invoice:

• Agree on a billing schedule: Confirm when you'll send invoices, whether weekly, monthly, or upon completion
• Set payment terms: Specify how long customers have to pay, typically 30 days. VAT-registered businesses must normally issue a VAT invoice within 30 days of providing goods or services
• Confirm payment methods: Clarify how customers can pay you so there's no confusion when the invoice arrives

Clear expectations prevent surprises and speed up payments.

What to include in your invoice

Every professional invoice needs these details to ensure you get paid on time. Research shows 42% of invoices are submitted with errors by small suppliers.

Business and customer details:

• Your business name and contact information
• Your customer's name and billing address

Invoice identifiers:

• A unique invoice number for tracking and tax purposes
• The invoice date and payment due date

Charges and payment:

• A clear description of products or services provided
• Itemised costs including any taxes or discounts
• The total amount due
• Clear instructions on how to pay

For tax purposes, you must keep VAT records for at least six years.

How to invoice

Creating an invoice means adding the essential information that documents the goods or services supplied and the payment due under what you agreed with the customer. Follow these steps to build a complete, professional invoice:

1. Open your invoice template: Start with a blank invoice template or create one in your invoicing software
2. Add the invoice date and a unique number: Use sequential numbering for tracking and legal purposes
3. Enter your business details: Include your name, address, and contact information
4. Add your customer's details: Include their name and billing address
5. Describe the work completed: Provide a clear breakdown of goods or services provided
6. List costs and taxes: Show itemised pricing including any applicable VAT
7. Include payment instructions: State the due date and explain how customers can pay

You can find more detail in the guide on how to make an invoice.

Ways to send an invoice

Email is the fastest and most common way to send invoices, but you have several options depending on your customer's preferences.

• Email: Attach your invoice as a PDF to prevent editing. This method is fast, creates a digital paper trail, and works for most customers.
• Online invoicing software: Send invoices directly from a platform like Xero for secure, professional delivery. Your customer gets a link to pay online instantly, and you can see when they've viewed it.
• Post: Send a paper invoice when customers require formal documentation. This method is slower and harder to track, but some businesses still prefer it.

Before you send, verify you're emailing the correct contact. A quick phone call after sending your first invoice confirms your customer received it and understands what's owed.

How to write an invoice email

Your invoice email should be short and professional. Your subject line determines how quickly the customer's accounts team processes your payment.

Use a clear subject line format:

• With purchase order: "Invoice 001 – PO ABC123 – due [date]"
• Without purchase order: "Invoice #001 – [Your Company] – Due [Date]"
• Project-based: "Invoice #001 – [Project Name] – Due [Date]"

Keep the email body simple. Here's an example:

"Here's invoice [number] from [company name], due on [date]. Please let me know if you have any questions. Thanks for your business."

The invoice itself contains the detailed description of goods or services. Contact your customer's accounts payable team to confirm their preferred subject line format.

When to send an invoice

Send your invoice as soon as the work is complete. The faster you invoice, the sooner you get paid, and the more stable your cash flow.

Invoice at these key moments:

• Upon completion: When orders are filled or tasks finished
• Project milestones: For large projects, bill for work completed to date
• Recurring services: Monthly or quarterly for subscriptions and retainers
• Immediate delivery: For products shipped or services rendered

Sending all invoices on the same day creates uneven income patterns. Spreading your invoicing throughout the month keeps cash flow steadier. Try these strategies for smoother cash flow:

• Bill weekly: Send invoices every week instead of batching them monthly
• Invoice immediately: Bill as soon as work is completed rather than waiting
• Automate scheduling: Use software to spread invoice dates evenly across the month

Track your invoices and payments

Tracking your invoices means monitoring which are paid and which are outstanding. Keeping track is essential for managing your cash flow and knowing when to follow up.

Online accounting software shows the status of all your invoices in one place, from sent and viewed to paid or overdue. When a customer pays, the software automatically matches the payment to the right invoice, saving you time on admin.

This gives you a real-time view of who owes you money, so you can act quickly when payments are late.

Overdue payment reminder email (or call)

Follow up quickly when invoices become overdue. Many invoices are paid late, and while 15% of firms avoid chasing unpaid bills for fear of losing future work, prompt, polite action prevents customers from developing bad payment habits.

Here's why quick follow-up matters:

• Resolves issues faster: Early contact identifies problems before they escalate
• Preserves relationships: Polite reminders maintain customer goodwill
• Sets expectations: Quick responses train customers to pay on time

If a payment is never made, you may eventually need to write off the invoice as a bad debt, which requires keeping a separate VAT bad debt account for debts older than six months.

Before the due date, send a gentle reminder:

"Please remember that [invoice number] is due tomorrow. You should have everything you need to process it, but let me know if any questions come up."

After the due date, act quickly:

"Invoice [number] was due yesterday but we don't have a record of payment. Please let me know when I can expect payment."

By phone: A short, friendly call can resolve things faster than email. Explain which invoice is late, then let them respond. You don't need to say a lot.

The gentle reminder email you don't have to write

Automated systems remind customers about invoices and follow up for you, eliminating the stress of chasing overdue payments manually. Here's how automation works:

• Tracks payments: Monitors your bank for incoming payments in real time
• Matches automatically: Links payments to the correct invoices without manual input
• Sends reminders: Delivers pre-written emails when payments become overdue
• Alerts you when needed: Notifies you only when multiple reminders are ignored

Send invoices with confidence

Getting paid starts with sending your invoice quickly and following up when needed.

• Invoice immediately: Send your invoice as soon as work is completed
• Follow up promptly: Contact customers about overdue payments within days
• Use automation: Let software handle routine reminders and tracking

Invoicing software can handle the admin so you can focus on your business. Get one month free and automate your invoice sending, tracking, and payment reminders with Xero.

FAQs on sending invoices

Find answers to common questions about sending invoices and getting paid.

What does it mean to send an invoice?

Sending an invoice means delivering a formal request for payment to your customer for products sold or services provided. It creates a record of the transaction for both parties.

How do you send someone an invoice?

Email your invoice as a PDF attachment, or send it through online invoicing software for instant payment options. Posting a paper copy works when customers require formal documentation, but it's slower to process.

How should you word an invoice email?

Keep your email clear and simple. Use a subject line like "Invoice #001 - [Your Company] - Due [Date]" so accounts teams can process it quickly. The body can be brief: "Here's my invoice for [service/product]. Thanks for your business."

When is the best time to send an invoice?

Send your invoice as soon as the work is complete or the product is delivered. The faster you invoice, the sooner you get paid. For ongoing projects, agree on a regular billing schedule, such as weekly or monthly.

What happens if a customer doesn't pay their invoice?

Start with a polite reminder email when the invoice becomes overdue. If you don't hear back, a friendly phone call often resolves things faster. Invoicing software can send automatic reminders for you, so you get paid without the awkward follow-up.