Sales Tax vs VAT: How to Calculate It
Two systems with the same goal
Governments tax consumption in two main ways. Sales tax is charged once, at the final sale to the consumer. Value-added tax (VAT), or GST in some countries, is charged at every stage of the supply chain, with businesses reclaiming the VAT they paid on their purchases. On an invoice, both appear as a percentage added to the net price.
How sales tax works
In systems such as the United States, sellers collect sales tax from the final customer and pass it to the tax authority. Rates vary by state and sometimes by city, and some goods and services are exempt. Business-to-business sales for resale are often exempt if the buyer provides a resale certificate, so keep those certificates on file.
How VAT and GST work
With VAT, you charge VAT on your sales (output tax) and reclaim the VAT you paid on business purchases (input tax), then pay the difference. The invoice must usually show your VAT number, the net amount, the rate and the VAT amount. Different rates can apply to different goods, such as standard, reduced and zero rates.
Adding tax to a net price
Multiply the net price by the rate to get the tax, then add it. For a net price of 100 at 20 percent, the tax is 20 and the total is 120. For several lines at the same rate, add the lines first and apply the rate once to the subtotal to avoid rounding differences. The tax calculator does this instantly.
Removing tax from a tax-inclusive price
If a price already includes tax, divide by one plus the rate. For 120 including 20 percent, the net price is 120 ÷ 1.2 = 100 and the tax is 20. Do not subtract 20 percent from 120, which gives 96 and the wrong tax figure. In InvoiceSeb, tick “Prices include tax” and the invoice extracts the tax for you.
Tax, discounts and shipping
Apply discounts before tax so that tax is charged on the amount the customer actually pays. Whether shipping and service fees are taxable depends on local rules: in many places they follow the tax treatment of the goods they relate to. If you are unsure, show shipping as a separate line and check the rule for your location.
Rounding and precision
Round tax to two decimals at the level required by your tax authority, usually on the invoice total or per line. Pick one method and use it consistently. Small rounding differences between your invoice and the customer’s records are a common cause of payment queries, so show the net, tax and gross amounts clearly.
Exports, reverse charge and exemptions
Exports and some cross-border business sales may be zero-rated or subject to a reverse charge, where the buyer accounts for the tax. These rules depend on the countries involved and the type of goods or services. State the reason for any exemption on the invoice, include both parties’ tax IDs when required and take professional advice for complex cases.
What to show on a tax invoice
A compliant tax invoice normally shows your name and tax ID, the customer’s details, the invoice number and date, a description of each item, the net amount, the tax rate and amount, and the total. Some countries require additional wording or a sequential numbering system. Keep invoices for the period your tax authority requires, often several years.
Registration thresholds, returns and record keeping
Most countries only require registration once your sales pass a threshold, although you may register earlier to reclaim tax on purchases. Once registered you file regular returns, often monthly or quarterly, reporting the tax you charged and the tax you paid. Keep copies of every invoice you issue and receive for the period your tax authority requires, usually between five and ten years, and store them in a way you can search. Reconcile your invoices to your returns before you file so that totals match, and set aside the tax you collect in a separate account because it is not your money.
Use calculators, then confirm the rules
Calculators remove arithmetic mistakes, but the rules about what to tax, at what rate and when to register differ everywhere. Use the invoice calculator to check totals, confirm the current rules with your tax authority or an accountant, and keep your records organised so that filing is straightforward.
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General information only, not legal, tax or financial advice.