Professional invoice with auto-calculating line totals, tax %, discount, and grand total.

About the Invoice Template

An invoice is the legal request for payment that closes the loop between delivering work and getting paid. Beyond the dollar figure, a compliant invoice needs a unique invoice number, an issue date, your business details, the client's billing information, a clear description of goods or services, and the payment terms. Missing any of these can delay payment or create disputes when a client's accounts-payable team tries to match the invoice against a purchase order.

This template handles the arithmetic that trips up most freelancers and small shops: line-item extension, tax on the taxable subtotal, and a flat discount applied to the bill. You enter each line's description, quantity, and rate; the tool multiplies quantity by rate for the amount, sums those amounts into a subtotal, applies your tax percentage, subtracts a dollar discount, and shows the total the client owes. It is built for service invoices, product sales, and mixed bills alike.

Before you enter your numbers

Confirm the contracting entity, billing address, purchase-order reference, currency, issue date, and due date with the customer.
Add the invoice number and payment instructions. Use the company/client text areas for additional legal or tax-registration details required in your location.

Assumptions and limits

The tax percentage applies to the whole subtotal. The dollar discount is subtracted after tax; there are no line-specific tax exemptions or multiple tax jurisdictions.
Amounts have no currency conversion. Displayed values use two decimals, while calculations retain JavaScript numeric precision. Check rounding against your accounting system.

Check your result

Two units at $100 create a $200 subtotal. With 10% tax and a $50 discount, tax is $20 and total is $170. Discount-before-tax would instead give $165; this tool does not use that method.

How the Invoice Template works

Each line's Amount equals Quantity multiplied by Rate. The Subtotal is the sum of every line's amount. Tax is calculated as Subtotal multiplied by the Tax percentage divided by 100, so a 10 percent rate on a $1,000 subtotal adds $100. The Discount field is a flat dollar amount, not a percentage, and it is subtracted after tax. The final Total is Subtotal plus Tax minus Discount.

Because the discount is applied to the post-tax figure in this tool, be deliberate about whether you are giving a pre-tax or post-tax concession; in many jurisdictions sales tax should be charged on the discounted price, so for tax-sensitive invoices reduce the line rates directly rather than using the flat discount box. The tax percentage applies to the entire subtotal, which assumes all lines are taxable. If you sell a mix of taxable products and non-taxable labor, split them onto separate invoices or set the rate accordingly.

Worked example

Say you bill a client for 20 hours of consulting at $75 per hour and one setup fee of $250. The two lines extend to $1,500 and $250, giving a subtotal of $1,750. With the tax percentage left at the default 10 percent, tax is $175. You offer a $50 loyalty discount. The total becomes $1,750 plus $175 minus $50, which equals $1,875. The client sees the subtotal, the $175 tax, the $50 discount, and the $1,875 amount due.

Tips & common mistakes

Assign sequential, never-reused invoice numbers (for example 2024-001, 2024-002). Gaps or duplicates make bookkeeping and audits harder.
State concrete terms like Net 15 or Net 30 and a due date rather than 'due on receipt' if you want predictable cash flow, and add a late-fee clause if your contract allows one.
Confirm whether your client requires a matching PO number on the invoice; enterprise accounts-payable systems reject invoices they cannot match.
Remember the discount box subtracts a flat dollar amount after tax, so for a percentage-off deal calculate the dollar figure first or lower the line rates.
Keep a copy of every invoice you send; you will need them for revenue reconciliation and tax filing at year end.

Invoice Template: frequently asked questions

Does the tax apply before or after the discount?

In this template tax is calculated on the full subtotal first, then the flat discount is subtracted. If your local rules require tax on the discounted amount, reduce the individual line rates instead of using the discount field.

Can I invoice for both products and services on one bill?

Yes. Add a line for each item or service with its own quantity and rate. Keep in mind the single tax percentage is applied to the whole subtotal, so mixing taxable and non-taxable items on one invoice can misstate the tax.

What is the difference between an invoice and a receipt?

An invoice requests payment for goods or services already delivered or about to be delivered; a receipt confirms payment has been received. Send an invoice to ask for money and a receipt once it clears.

How do I handle a deposit or partial payment?

Enter the deposit as a negative-rate line or subtract it from the total on a follow-up invoice noting the amount already paid, so the balance due is clear to the client.

What payment terms are standard for small businesses?

Net 30 is common for B2B work, but Net 15 or due-on-receipt speeds up cash flow for smaller vendors. Whatever you choose, state the exact due date so there is no ambiguity.

Use the result in your next decision

Cash Flow Forecast: Forecast when the invoice will actually be paid, not only when it was issued.
Profit & Loss Statement (Monthly): Separate billed revenue from business profitability.

Sources and further reading

These references explain the specified topic; they are not endorsements or evidence that a professional has reviewed this tool.

GOV.UK: Invoicing and taking payment — An example of jurisdiction-specific invoice requirements. UK guidance is not a statement of rules elsewhere.

Invoice Template

Invoice

Company Info

Client Info

Scope and reference context