How to send an invoice (and what to do if it’s ignored)

Published Monday 29 September 2025

Table of Contents

• What to include in your invoice
• When to send an invoice
• How to send your invoice
• Send invoices instantly after completing work
• How to write an invoice email
• Payment options that speed up collection
• Track your invoice status and automate reminders
• Overdue payment reminder email (or call)
• Take your invoicing online with Xero
• FAQs on sending invoices

Key Takeaways

• Send invoices immediately after completing work rather than waiting for weekly or monthly billing cycles to improve cash flow and reduce payment collection time by up to 40%.
• Use email delivery with PDF attachments and include online payment options like "Pay Now" buttons to enable instant payments and reduce collection time by up to 50%.
• Implement automated invoice tracking and reminder systems to eliminate manual follow-up work, improve collection rates by 45%, and maintain consistent professional communication with customers.
• Contact customers within 24-48 hours of missed due dates through direct phone calls or email to resolve 85% of payment issues immediately and recover 67% of late payments.

What to include in your invoice

Invoice creation transforms your work into a professional payment request that customers can process quickly.

Pre-invoice communication sets clear expectations before you send any bills. This prevents payment delays and customer confusion.

Discuss these billing details upfront:

• Invoice timing: When you'll send invoices (weekly, monthly, or project completion)
• Payment terms: How long customers have to pay
• Payment methods: What options you accept

Clear communication eliminates surprises that can delay payments.

Essential invoice elements include:

• Business information: Your name, address, and contact details
• Customer details: Client name and billing address
• Invoice specifics: Unique invoice number and date
• Work description: Clear details of goods or services provided
• Payment terms: Total amount, due date, and payment methods
• Tax information: Any applicable sales tax or VAT

When you send a complete, professional invoice, you get paid 30% faster.

When to send an invoice

Invoice timing directly impacts your cash flow and payment speed. Send invoices immediately when work is complete to get paid faster.

Common invoice schedules:

• Project completion: Send immediately after delivering work or products
• Milestone billing: Invoice at project phases for large jobs
• Recurring services: Bill monthly or weekly for ongoing work
• Subscription billing: Automate recurring invoices for regular services

Cash flow optimization:

Send invoices at different times during the month instead of all at once. This helps you keep money coming in and avoids gaps in your cash flow.

Best practice: Invoice weekly rather than monthly when possible. Customers pay 40% faster on weekly invoices.

How to send your invoice

Email delivery is the fastest, most reliable way to send invoices. Email invoices arrive instantly and can't get lost in the mail.

Why email is better than postal mail

• Speed: Instant delivery vs. 3-5 days
• Reliability: No risk of lost mail
• Accuracy: Email addresses are easier to verify than postal addresses
• Cost: Free vs. postage costs

Email best practices:

• Follow up: Call after sending your first invoice to confirm receipt
• File format: Attach your invoice as a PDF to prevent editing
• Online payment: Add payment links so your customers can pay instantly

Online invoicing lets customers pay immediately with credit cards, debit cards, or automated clearing house (ACH) transfers, reducing payment time by up to 50%.

Send invoices instantly after completing work

The sooner you send your invoice, the sooner you can get paid. Instead of waiting to do weekly or monthly billing, create and send an invoice as soon as a job is finished. Use invoicing software on your computer or mobile device to bill customers on the spot.

This simple habit helps improve your cash flow and reduces the time you’ll spend chasing payments later

How to write an invoice email

Invoice email structure ensures your bills get processed quickly by accounting departments. A clear subject line and professional message speed up payment approval.

Subject line best practices:

• Include invoice number: "Invoice #12345 - [Your Company Name]"
• Add purchase order: Reference PO numbers when available
• Specify due date: "Due [Date] - Invoice #12345"

Email template:

"Here’s invoice #[number] from [Company Name], due on [date]. You’ll find payment details in the attached PDF. Thanks for your business."

Keep it simple: Detailed work descriptions belong on the invoice itself, not in the email body.

Payment options that speed up collection

Make it easy for your customers to pay you. The more convenient the payment process, the less likely you are to face delays. Offer a variety of payment methods to suit different customer preferences.

Popular options that help you get paid faster include:

• online payment gateways such as Stripe or PayPal
• credit and debit card payments
• automated clearing house (ACH) bank transfers
• Use online payment gateways such as Stripe or PayPal
• Accept credit and debit card payments
• Accept automated clearing house (ACH) bank transfers

Including a 'Pay Now' button directly on your online invoice is one of the most effective ways to encourage immediate payment.

Track your invoice status and automate reminders

Automated invoice reminders eliminate the stress of chasing payments while improving collection rates by 45%. Software handles follow-up so you can focus on your business.

How automation works:

• Payment tracking: Software monitors bank deposits and matches payments to invoices
• Automatic reminders: Pre-written emails send on due dates
• Escalation sequences: Multiple reminders at set intervals
• Exception handling: You only handle cases requiring personal attention

Key benefits:

• Time savings: Reduces follow-up work by 80%
• Consistency: Never miss sending a reminder
• Professional tone: Maintains customer relationships
• Better results: Automated systems collect payments 30% faster

Overdue payment reminder email (or call)

Overdue invoice follow-up recovers 67% of late payments when done promptly. Act within 24-48 hours of the due date to maintain good payment habits.

Pre-due reminder template:

"Invoice #[number] is due tomorrow. You should have everything you need to process payment, but let me know if you have any questions."

Overdue payment template:

"Invoice #[number] was due yesterday and I haven’t received payment. Please let me know when you expect to pay."

Phone call strategy:

You can resolve 85% of payment issues right away with a phone call. Keep your calls brief and direct:

• State the overdue invoice number
• Ask when you can expect payment
• Ask your customer to explain the delay
• Avoid filling awkward silences

Timing matters: Contact customers within 48 hours of the due date for best results.

Take your invoicing online with Xero

Smart invoicing practices get you paid faster and improve cash flow. Send invoices immediately after completing work, use professional templates, and automate follow-up to reduce payment delays.

Key takeaways

• Send immediately: Invoice right after work completion
• Use email delivery: 50% faster than postal mail
• Automate reminders: Improve collection rates by 45%
• Professional formatting: PDF invoices get paid 30% faster

Xero's invoicing software handles everything from professional templates to automated reminders, helping small businesses get paid faster. Try Xero for free and see how easy invoicing can be.

FAQs on sending invoices

Here are common questions and answers small business owners may have when they send out invoices.

What does it mean to send an invoice?

Sending an invoice means you are formally requesting payment from a customer for goods or services you have provided. It's a bill that details what the customer owes, when it's due, and how they can pay.

How can I send an invoice and get paid instantly?

The fastest way to get paid is by using online invoicing software. You can email an invoice with a 'Pay Now' button that allows customers to pay immediately using a credit card, debit card, or bank transfer. This eliminates the delays of manual payments.

What's the best format to send an invoice in?

You should send your invoices as a PDF file. This format is professional, easy for anyone to open, and can’t be easily edited, so your invoice details stay secure.