How to Prepare a Customer Invoice

If you're an entrepreneur who sells a product or provides a service to clients before they pay you, a customer invoice is the ideal way for you and the client to know exactly how much money is owed for the job or item(s) purchased. A customer invoice documents the quantity and cost of what you provided, shows any sales tax, discounts and most importantly, tells customers how and when you expect to be paid. Whether your invoice is electronic or on paper, this small business bookkeeping tool is the best way to keep your business running profitably.


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    Write or type your company's contact information on a sheet of paper, spreadsheet or other electronic record keeping system. Remember to include an email address and phone number where they can contact you with questions.
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    Create an original customer invoice number using letters, numbers or both. A customer invoice number can be as simple "Job-001" or more complex, such as "Smith-Job-001." The second example is useful for repeat customers because it includes their last name along with a job number. Future invoices should have original, sequential job numbers, which make sorting the client's job histories easier.
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    Date the invoice. The sooner you begin invoicing clients for work or services you provided, the sooner you can get paid.
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    Describe the work you performed. Use separate lines to itemize details about each service or product you provided. Include a description of the type and quantity of materials that were used. Service providers should offer clear details about the scope of the work performed and how many hours were spent on each segment of the work.
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    Add up the total quantities of each material, product and/or service you provided. This is called the subtotal.
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    Factor in sales tax based on taxable items you provided. If you are reselling items, you need to charge customers sales tax for most tangible products. Check with your state franchise tax board for licensing procedures and applicable sales tax rates.
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    Tally the subtotal and sales tax to arrive at the final job cost. Include this figure at the bottom of the invoice. Always ensure the numbers are in legible, boldface type so customers know exactly how much to pay.
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    Indicate payment terms that describe when you want to get paid. Examples small business owners use include NET 15 or NET 30, which means payment is due in 15 or 30 days. If you want to be paid when the customer receives your invoice, write "Due on Receipt."
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    Tell how you want to get paid. Whether you expect payment as cash on delivery (COD), cash, check or credit card, let customers know what methods of payment are accepted.


  • If your occupation requires special certification or licensing, include your license or certificate number in the contact information area. This assures customers that you are a legitimate professional with the basic qualifications needed to perform the work.


  • Failure to clearly indicate the depth of the work you performed may lead to miscommunication about job expectations. When invoicing clients, you'll find it more advantageous to include more detail rather than less.

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Categories: Sales