# What to include on an invoice: the complete checklist. By Roy van Oeteren, founder · Updated October 17, 2026 · 6 min read A professional invoice includes the word “invoice”, a unique invoice number, the issue date and due date, your business name and contact details, your client's name and address, an itemized list of what you are charging for, any sales tax, the total due, and the payment instructions. In the US, there is no single federal form that every invoice must follow, but those items are what clients, accountants and the IRS expect to see. Use the checklist below, and check your state's rules for anything extra. ## The must-have items If an invoice is missing one of these, expect questions or a delay in payment. | Item | What to write | | --- | --- | | Title | The word “Invoice” at the top | | Invoice number | A unique, never-repeated number, such as INV-1042 | | Invoice date | The day you issue it | | Due date | The actual date, such as November 16, 2026 | | Your details | Business or personal name, address, email, phone | | Client details | Company name, contact person, billing address | | Line items | Description, quantity, rate and amount for each | | Totals | Subtotal, tax, discounts, total due | | Payment instructions | How to pay and where to send the money | ## Items that help you get paid faster These are not strictly required, but each one removes a reason to delay. - Payment terms such as due on receipt, Net 15 or Net 30. See [what Net 30 means](https://jiffy-invoice.com/guides/net-30-payment-terms). - A PO number or project reference, if the client gave you one. Many finance teams cannot process an invoice without it. - A payment link or clear bank details, so the client can pay without writing back to ask. - A late fee policy, stated before the invoice becomes overdue. Read the [late fees guide](https://jiffy-invoice.com/guides/late-payment-fees) first. - A short thank-you or note with anything unusual, such as why the total differs from the estimate. - Your tax ID or EIN, when the client requires it for their records. ## Sales tax: when it belongs on the invoice If you are registered to collect sales tax, show it as its own line with the rate, and add your registration number if your state requires it on invoices. If you do not charge tax, because your service is not taxable or the sale is out of state, it is clearer to say so than to leave the line out. Sales tax rules in the US are set by each state, and they differ for services, goods and digital products. They also change. This guide cannot tell you what applies to you, so check your state's department of revenue or ask your accountant. A [sales tax or VAT calculator](https://jiffy-invoice.com/vat-calculator) helps with the arithmetic, not with the rules. ## What to leave off - Your full Social Security number. Use an EIN, or send a W-9 through a safe channel. - Your full bank card number. Never put a card number on an invoice. - Internal notes about margin, hours you did not bill or discounts you are thinking about. - Claims you cannot back up, such as “guaranteed results”. - Anything that looks like a legal threat on a first invoice. A friendly reminder works better. ## Invoice checklist you can paste into a note Run through this just before you send. **Before I hit send** > [ ] Says “Invoice” and has a number I have not used before > [ ] Invoice date and a real due date > [ ] My name, address, email and phone > [ ] Client name, contact person and billing address > [ ] PO number or project name, if the client has one > [ ] Every line has a description, quantity, rate and amount > [ ] Sales tax shown (or noted as not applicable) > [ ] Deposits and credits subtracted, total due is correct > [ ] Payment instructions and payment terms > [ ] Late fee wording, if I charge one > [ ] Sent to the person who approves payments ## Do invoices for different jobs need different things? The checklist above is the base. A few kinds of work add their own items. A contractor may add materials, labor and a project address. A photographer may add a usage license. A consultant may add a statement of work number. Add what your client expects to see, and keep every line understandable to someone who was not on the project. If you bill clients abroad, add your client's country and the currency, and check whether their tax rules (such as VAT) apply. For a first layout, the [invoice templates](https://jiffy-invoice.com/invoice-templates) show how different trades arrange these items. ## Keep a copy Keep every invoice you send, in a folder you can find in a year. Your accountant will want them, and so will you if a client disputes a charge. How long to keep business records depends on your situation and your state, so ask your accountant. Invoicing software keeps them for you, with the status of each one, so you can see what is paid and what is open. ## Get every item on the page, every time. The free invoice generator has fields for all of these, and calculates the totals as you type. Save the result as a PDF. [Open the free invoice generator](https://jiffy-invoice.com/invoice-generator) ## Questions people ask ### Is an invoice without a number still valid? Probably yes, as a document, but it is a bad idea. A number is how both sides find and match the invoice later, and your accountant will expect one. ### Do I need to put my EIN or SSN on an invoice? Not usually. Some clients ask for a tax ID to pay you; give an EIN, or a W-9 through a secure channel, rather than printing your Social Security number on the invoice. ### Does an invoice need a signature? No. A signature is not required on an invoice. Quotes and contracts are different: there, a signature shows the client agreed. ### What is the difference between an invoice and a bill? They are the same document from two sides. You send an invoice; your client receives it and treats it as a bill to pay. ## Related guides - [How to write an invoice, step by step](https://jiffy-invoice.com/guides/how-to-write-an-invoice) - [Invoice vs receipt: what is the difference?](https://jiffy-invoice.com/guides/invoice-vs-receipt) - [What does Net 30 mean? Payment terms explained](https://jiffy-invoice.com/guides/net-30-payment-terms) [Invoicing guides](https://jiffy-invoice.com/guides) Source: https://jiffy-invoice.com/guides/what-to-include-on-an-invoice