How to Write an Invoice (Easy Guide, Examples, & Template)

Writing an invoice is a crucial skill for freelancers, small business owners, and entrepreneurs.

Here is a quick answer for how to write an invoice:

Write an invoice by choosing a template, adding your business and client information, assigning an invoice number and date, listing goods or services provided with their costs, specifying payment terms, calculating the total amount due, and including any additional notes before sending it.

In this guide, we’ll explore everything you need to know about writing an invoice.

What Is an Invoice?

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Well-designed invoice on a sleek desk with office supplies -- How to Write an Invoice
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An invoice is a document sent by a seller to a buyer requesting payment for goods or services provided.

It includes a detailed list of the products or services, their prices, payment terms, and other relevant information.

Invoices are essential for bookkeeping, tax purposes, and maintaining a professional relationship with clients.

Key Components of an Invoice

  • Header – Your business name and contact details.
  • Invoice Number – A unique identifier for the invoice.
  • Date – The date the invoice is issued.
  • Client Information – Name and contact details of the client.
  • Description of Services/Goods – Detailed list of what you’re billing for.
  • Amount Due – Total cost, including taxes and discounts.
  • Payment Terms – When and how the payment should be made.

Types of Invoices

Different businesses and transactions require various types of invoices.

I’ve personally used every single one of these types, so I’ll add my insights and thoughts as we go over them.

Here are some common ones:

Standard Invoice

A standard invoice is the most common type used by businesses for regular transactions.

It includes all the essential components needed to request payment from a client.

These components typically include the seller’s and buyer’s contact information, a unique invoice number, the date of issue, a detailed list of goods or services provided, individual costs, and the total amount due.

Standard invoices are versatile and can be used for one-time purchases or services.

Credit Invoice

A credit invoice, also known as a credit memo, is issued when a refund or credit is due to the client.

This type of invoice is used to document returns, overpayments, or adjustments to previous invoices.

It reduces the amount the client owes or can be applied to future purchases.

Credit invoices include the original invoice details, the reason for the credit, and the amount being credited.

They are essential for maintaining accurate financial records and ensuring transparency in transactions, helping to build trust with clients by showing adjustments are properly documented.

Debit Invoice

A debit invoice, or debit memo, is sent when additional charges apply to a previous invoice.

This could be due to extra services provided, corrections to undercharged amounts, or other additional costs that were not included in the original invoice.

Debit invoices increase the amount the client owes and include detailed explanations for the additional charges.

Like credit invoices, debit invoices help maintain accurate financial records by documenting changes to the original transaction.

They are crucial for businesses that need to adjust billing amounts post-transaction and ensure all services or products are adequately billed.

Proforma Invoice

A proforma invoice is an estimate provided before the actual delivery of goods or services.

It outlines the items or services to be provided, their estimated costs, and other relevant details, giving the client a clear understanding of what to expect.

Unlike a standard invoice, a proforma invoice is not a demand for payment but a preliminary bill of sale.

It helps clients budget for the upcoming expense and facilitates smooth transactions by clarifying terms and costs in advance.

Proforma invoices are often used in international trade to declare the value of goods for customs.

Recurring Invoice

A recurring invoice is used for ongoing services, such as subscriptions, memberships, or retainer agreements.

This type of invoice is automatically generated and sent at regular intervals (weekly, monthly, annually) based on the agreed-upon terms.

Recurring invoices streamline the billing process for businesses providing continuous services, ensuring consistent cash flow and reducing administrative effort.

They include all standard invoice components but are designed to be easily repeatable.

Businesses use recurring invoices to manage long-term client relationships efficiently, offering clients the convenience of predictable, regular billing.

Timesheet Invoice

A timesheet invoice details hours worked, commonly used by freelancers, consultants, and contractors.

It breaks down the billable hours spent on specific tasks or projects, the hourly rate, and the total amount due.

Timesheet invoices are essential for service-based professionals who charge by the hour.

They provide transparency and clarity for clients, showing exactly how time was spent and justifying the billed amount.

Accurate timesheet invoices help maintain client trust and ensure timely payment for hours worked.

They often include additional information like project descriptions and time logs.

Mixed Invoice

A mixed invoice combines multiple types of charges, such as products and services, into one document.

This is useful for businesses that offer both goods and services, providing a comprehensive billing solution.

Mixed invoices detail each item or service separately, including quantities, unit prices, and total costs, then sum them up for a grand total.

They help streamline the billing process by consolidating different charges into a single invoice, making it easier for clients to review and pay.

Mixed invoices are ideal for businesses with complex billing needs, ensuring all charges are accurately captured and presented.

How to Write an Invoice (Step-By-Step)

Creating a professional invoice involves several steps. Follow this guide to ensure all essential details are included.

Step 1: Choose an Invoice Template

Select a template that suits your business needs.

You can find free templates online or use invoicing software.

A well-designed template saves time and ensures consistency across all your invoices.

Look for templates that include customizable fields for all necessary information, such as business details, client information, itemized lists, and payment terms.

Many online platforms offer a variety of styles, so you can choose one that aligns with your brand image.

Using a template also helps maintain a professional appearance, which can enhance your credibility with clients.

Step 2: Add Your Business Information

Include your business name, logo, address, phone number, and email.

This information helps clients identify the sender and provides them with multiple ways to contact you if they have questions.

Adding your logo helps reinforce your brand identity, while including complete contact details ensures transparency and trust.

It also makes it easier for clients to save your information for future reference.

Double-check that all information is accurate and up-to-date to avoid any confusion or delays in communication.

Step 3: Assign an Invoice Number

Generate a unique invoice number for tracking purposes.

Use a sequential system to stay organized. This number is crucial for both your records and your client’s, as it helps track payments and manage accounts efficiently.

A common format includes a combination of numbers and letters, such as “INV-001” or “2024-001”.

Ensure your numbering system is consistent and easy to follow.

Avoid using duplicate numbers, as this can lead to confusion and potential errors in your accounting records.

Step 4: Include Client Details

Add the client’s name, address, and contact information.

This ensures the invoice reaches the right person and can be processed without delay.

Accurate client details also facilitate better record-keeping and follow-up communication.

Make sure to verify the spelling of names and the accuracy of addresses to avoid any issues.

Including client contact information like email and phone number provides additional ways to follow up if payment is delayed or if there are any questions about the invoice.

Step 5: List the Goods or Services Provided

Describe each item or service, including quantity, unit price, and total cost.

Be clear and detailed to avoid confusion. Use specific descriptions that accurately reflect what was provided to the client.

For example, instead of listing “Consulting Services,” specify “Consulting Services – 10 hours at $50/hour.”

This level of detail helps the client understand exactly what they are being charged for and can reduce disputes.

Itemized lists also make it easier to verify that all billed services or products have been accounted for.

Step 6: Add Payment Terms

Specify the payment due date, accepted payment methods, and any late fee policies.

This sets clear expectations for the client and helps ensure timely payment.

Common payment terms include “Net 30,” meaning payment is due 30 days from the invoice date.

Be sure to outline any late fees or penalties for overdue payments to encourage prompt payment.

Also, provide information on how clients can make payments, such as bank transfer details, online payment links, or mailing addresses for checks.

Step 7: Calculate the Total Amount Due

Sum up all charges, including taxes and discounts.

Ensure the total is accurate to prevent any disputes or delays in payment.

Clearly display the subtotal, any applicable taxes, and the final total amount due. If you offer discounts, itemize these as well so clients can see the original amount and the discount applied.

Double-check your calculations to ensure accuracy, as errors can undermine your professionalism and delay payments.

Step 8: Include Additional Notes

Add any relevant notes, such as thank you messages or special instructions.

These notes can personalize your invoice and provide important information to the client. For example, you might thank the client for their business or provide instructions on how to view and pay the invoice online.

Additional notes can also be used to clarify any special terms or conditions that apply to the invoice.

Keep these notes concise and relevant to avoid overwhelming the client with too much information.

Step 9: Review and Send the Invoice

Double-check all details before sending the invoice to the client via email or mail.

Ensure that all information is correct, from the client’s details to the itemized list of services or goods.

An accurate invoice reflects professionalism and can prevent payment delays.

Consider saving the invoice as a PDF to maintain formatting consistency when sending it electronically.

If mailing, use a reliable service to ensure timely delivery. After sending, follow up to confirm receipt and answer any questions the client might have.

Check out this video about how to write an invoice:

YouTube Video by Accounting Stuff — How to Write an Invoice

How Do I Write a Simple Invoice?

A simple invoice includes the basic components necessary for billing. Here’s how to create one.

Step 1: Business and Client Information

Start with your business name, address, and contact details. Follow with the client’s information.

This sets the foundation for your invoice and ensures both parties are clearly identified.

Accurate information is crucial for record-keeping and follow-up communication.

Make sure to verify the client’s details to avoid any delays or miscommunications. Providing complete contact information for both parties helps maintain transparency and professionalism.

Step 2: Invoice Number and Date

Assign a unique invoice number and include the date of issue.

This helps in tracking and organizing your invoices. Use a sequential numbering system to keep records orderly.

The date of issue is important for calculating payment due dates and any potential late fees.

Ensure both the invoice number and date are prominently displayed at the top of the invoice for easy reference.

Step 3: Description and Cost

List the services or products provided with their respective costs.

Be specific and clear in your descriptions to avoid any confusion. For each item or service, include the quantity, unit price, and total cost.

This breakdown helps the client understand what they are being charged for and can prevent disputes.

Detailed descriptions also provide a transparent record of the transaction for both you and the client.

Step 4: Total Amount Due

Add up all charges and display the total amount due.

Ensure this amount is clearly visible and easy to find on the invoice. Double-check your calculations to ensure accuracy.

An accurate total helps prevent payment delays and builds trust with your client.

Include any applicable taxes or discounts in the total amount. Clear and accurate totals streamline the payment process and minimize back-and-forth communications.

Step 5: Payment Terms

Specify when and how the payment should be made.

Include details such as the payment due date, accepted payment methods, and any late fees or discounts for early payment.

Clear payment terms help set expectations and encourage timely payment.

Providing multiple payment options can make it easier for clients to pay promptly. Clearly stating the terms helps avoid misunderstandings and ensures both parties are on the same page.

Example of a Simple Invoice

javascriptCopy codeBusiness Name
Phone Number

Invoice Number: 001
Date: 05/14/2024

Client Name
Client Address

Description          Quantity      Unit Price      Total
Service A                2                 $50                 $100
Service B                1                 $75                 $75

Total Amount Due: $175
Payment Due: 05/21/2024

How to Write a Handwritten Invoice?

Handwritten invoices are suitable for small transactions or on-the-go billing.

Here’s how to create one:

Step 1: Use an Invoice Book

Purchase a pre-printed invoice book with carbon copies for record-keeping.

These books are readily available at office supply stores and come in various formats.

Using an invoice book ensures you have a physical copy of each invoice for your records.

The carbon copy provides a duplicate that you can keep for your records, which is especially useful if you need to reference the invoice later or provide proof of the transaction.

Step 2: Fill in Business Details

Write your business name and contact information at the top.

This helps the client identify who the invoice is from and provides them with contact information if they have questions.

Make sure your writing is clear and legible to avoid any confusion.

Including your address, phone number, and email ensures the client can easily reach you for any inquiries or payments.

Consistently using the same format for your business details helps maintain a professional appearance.

Step 3: Add the Client Information

Include the client’s name and contact details.

This ensures the invoice is directed to the correct person or department and helps with tracking and follow-up.

Verify the accuracy of the client’s details before writing them down to prevent any delays or issues with payment.

Clear and accurate client information also helps in maintaining organized records and simplifies the follow-up process if needed.

Step 4: Describe the Products/Services

List the items or services provided, including quantities and prices.

Be specific and clear to avoid any misunderstandings.

Each line should detail one item or service, the quantity provided, the unit price, and the total cost for that line.

Clear descriptions help the client understand what they are being billed for and can prevent disputes.

Detailed listings also make it easier to verify the accuracy of the invoice against the services or products delivered.

Step 5: Calculate the Total

Sum the costs and write the total amount due. Double-check your calculations to ensure they are correct.

Clearly display the total amount due at the bottom of the invoice.

Accurate calculations help prevent payment delays and maintain your professionalism.

Including any applicable taxes or discounts in the total ensures the client knows the exact amount they need to pay.

Clear totals also facilitate smooth and timely payments.

Step 6: Include Payment Terms

Specify payment terms and due date.

Clearly state when the payment is due and what payment methods are accepted.

Including any penalties for late payments or discounts for early payments can encourage timely payment.

Clear payment terms help set expectations and ensure both parties are on the same page. Providing this information upfront prevents misunderstandings and facilitates smooth transactions.

Example of a Handwritten Invoice

lessCopy code[Your Business Name]
[Your Address]
[Your Phone Number]

Invoice Number: [001]
Date: [05/14/2024]

Client Name: [John Doe]
Client Address: [123 Client St]

Description              Quantity          Unit Price          Total
Product A                  3                      $20                      $60
Service B                  1                      $100                    $100

Total Amount Due: $160
Payment Due: 05/21/2024

Free Invoice Template

Using a free invoice template can save time and ensure your invoices look professional.

Here are some benefits and sources for free templates:

Benefits of Using Free Invoice Templates

  • Time-Saving – Pre-designed templates simplify the invoicing process.
  • Professional Appearance – Templates offer a polished look.
  • Consistency – Maintain uniformity in your invoices.

Where to Find Free Templates

  • Microsoft Office – Word and Excel templates.
  • Google Docs – Easy-to-use templates.
  • Invoicing Software – Many offer free templates for download.

Example Free Invoice Template

[Your Business Name]
[Your Address]
[Your Contact Information]

Invoice Number: [001]
Date: [05/14/2024]

Client Name: [Jane Smith]
Client Address: [456 Client Ave]

Description Quantity Unit Price Total
Service A 2 $50 $100
Service B 1 $75 $75

Subtotal: $175
Tax (10%): $17.50
Total Amount Due: $192.50
Payment Due: 05/21/2024

Final Thoughts: How to Write an Invoice

Invoices are not just about getting paid; they also reflect your business’s credibility and organization.

Use this guide and the provided examples to streamline your invoicing process and ensure timely payments.

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