How to send an invoice: Complete guide with examples

Sending an invoice isn’t just about listing what’s owed. Done right, it sets clear expectations, reduces late payments, and keeps your cash flow steady.

You typically send an invoice when:

• Completing a project
• Delivering products
• Fulfilling a sales order
• Reaching project milestones or requesting a deposit
• Providing ongoing or recurring services

But as many small business owners and freelancers know, chasing down unpaid invoices can be frustrating. Sending invoices properly from the outset reduces delays, builds trust, and helps maintain steady cash flow.

What is an invoice?

An invoice is a formal request for payment that records the details of a sale between a business and a customer. It’s both proof of the transaction and a tool for managing finances.

Invoices play an important role because they:

• Facilitate payments
• Track sales and revenue
• Provide proof of purchase or delivery
• Reinforce agreed-upon payment terms
• Serve as tax and audit documentation

Key components of a standard invoice

Although there can be some variance based on the specifics of your business, professional invoices generally should include these elements:

• Invoice number: A unique number to help identify and track
• Dates: Both the invoice date and the due date
• Your business information: Including your name, address, phone number, email address, and logo
• Customer information: Their name, address, and contact information
• Payment terms: Acceptable payment methods, contractual terms (like net 30 or due upon receipt), and information about late fees or early payment discounts
• Itemized charges: A list of the products or services with descriptions, quantities, and prices
• Total amount due: Including taxes, fees, and discounts

Invoices serve as a legal document of a financial transaction. They can serve as a source of truth in the event of a customer dispute. They also help you maintain accurate financial records for tax purposes, potential audits, and effective cash flow management.

When should you send an invoice?

Planning when to send an invoice is just as important as how you send it. The right timing keeps cash flow predictable and strengthens customer relationships.

Here are five common scenarios:

1. After completing a project: For one-time work like freelance design or consulting, invoice immediately after the project wraps
2. When a product is delivered: Invoice when the item ships or once the customer receives it, depending on your agreement
3. At project milestones: For larger projects, send invoices at agreed checkpoints (e.g., 50% completion or upon deliverables)
4. For recurring services: Ongoing services, such as IT or digital marketing, are typically invoiced monthly, quarterly, or on the contract schedule
5. For deposits or advances: If upfront payment is required, invoice as soon as the contract is signed

Why invoice timing matters

Invoice timing directly affects cash flow. The sooner you invoice, the sooner you get paid, and consistency reduces the hassle of chasing clients. Prompt, predictable invoicing also signals professionalism, reinforces agreed terms, and builds long-term trust with customers.

How to prepare an invoice

Sending an invoice seems simple until payment is delayed because of a missing detail. A structured invoicing process reduces back-and-forth, sets clear expectations, and ensures clients have everything they need to pay on time.

These are the six essential pieces to include when creating an invoice:

1. Add your business details

Include the following information about your business:

• Business name
• Address
• Contact information, including phone number and email
• Your logo or any additional branding

This is crucial so that your customer knows who the invoice is from and how to contact them if they have any concerns.

2. Add you client’s details

Who are you directing this invoice to? List your client’s business name, contact person or department, address, phone, and email. Always double-check to ensure you have the correct contact information and you’re directing it through the proper channels.

3. Include invoice number and dates

Assign a unique invoice number for tracking. Always include both the issue date and the payment due date.

The invoice number and date are used for organizing and tracking invoices. Try to create invoices with sequential numbers for easier tracking.

4. Describe goods or services

Provide a clear breakdown of what you’re billing for. Each line item should include:

• Brief description
• Quantity
• Unit price
• Subtotal

This is the real meat of your invoice: Which products or services are you seeking payment for? It justifies your invoice and gives transparency around pricing.

5. Set amount due and payment terms

State the total balance, including taxes, fees, or discounts. Reiterate agreed terms, such as:

• Payment due date: e.g., Net 30 payment terms
• Late fees: Penalties for overdue payments
• Deposits or advances: Upfront amounts required before work begins

Example: Invoices are due within 15 days. Late payments will incur a 3% monthly interest charge.

6. Choose a payment method

The easier it is for clients to pay, the faster you’ll receive funds. Offering a variety of payment options removes friction and helps avoid processing delays.

Common options include:

• Bank transfer (ACH/Wire): Secure and reliable for large transactions
• Credit card: Fast, but may include processing fees
• Digital platforms (PayPal, Stripe): Convenient, especially for international payments
• Checks: Still used in some industries but slower to process

For corporate clients, ACH and credit card payments speed up approvals. For international clients, platforms like PayPal can simplify currency conversions.

Common mistakes to avoid

Before you send an invoice, double-check for:

• Missing contact information
• Absent or duplicate invoice numbers
• Vague item descriptions
• Missing payment terms or due dates
• Typos or math errors

Even small mistakes can slow down payments and appear unprofessional.

Methods for sending an invoice

The way you deliver an invoice affects how quickly it’s received and paid. Here are three common methods to consider:

1. Email

Email is one of the fastest and most cost-effective ways to send invoices. Many invoicing platforms let you generate and send PDF invoices directly, making it easy to track delivery and automate reminders.

A well-written email also helps ensure your invoice gets noticed. Here’s a simple example:

Subject: Invoice #1023 from XYZ Consulting—Due Nov 30, 2025

Dear [Client’s Name],

Please find attached Invoice #1023 for services rendered. Payment is due by Nov 30, 2025. Let us know if you have any questions.

Thank you for your business. [Your Name] | [Your Business Name]

2. Invoicing software

Cloud-based invoicing tools streamline the process by handling creation, sending, and tracking in one place. Features often include:

• Automatic invoice creation and delivery
• Recurring billing for repeat customers
• Payment reminders and tracking

3. Physical mail

Some industries, like government agencies or law firms, still require paper invoices. While reliable, this method is slower and lacks tracking.

If you mail invoices, include a professional cover letter, use company letterhead, and send early enough to account for delivery and processing times.

Best practices for sending invoices

Follow these invoicing best practices to ensure your invoices are received and paid promptly:

1. Double-check recipient details: Verify the client’s name, business, email, and address before sending. Small errors can delay payment.
2. Set clear terms and due dates: Always state payment terms (e.g., Net 15, Net 30) and include a specific due date. Clear deadlines prevent confusion.
3. Follow up on late payments: If a payment is overdue, send a polite reminder the day after it’s due. Follow up again a week later, then escalate to a phone call if needed.
4. Use automated tools: Invoicing software reduces errors, sends reminders, and makes it easier to track payments
5. Keep organized records: Store all invoices securely for tracking, tax purposes, and audits. Accurate records save time when reconciling accounts.

Optimize invoice management with Ramp

Keeping up with invoices is about precision, efficiency, and full visibility. Ramp’s automated invoice management system streamlines the entire process, reducing manual work so your team can focus on higher-value tasks.

With AI-powered OCR, automated approvals, and seamless ERP integration, Ramp removes data entry bottlenecks, speeds up processing, and improves accuracy at every stage while also providing a centralized payment hub that supports ACH, wire, check, and card payments.

Manual invoice management slows businesses down. See how Ramp’s invoice automation software can transform your workflow—or explore our interactive demo today.