Sales tax is a consumption tax charged on specified sales of goods and, in some jurisdictions, services. It is generally imposed at the point of sale to the final consumer, with the seller collecting the tax from the customer and remitting it to the relevant tax authority. Unlike a tax on business profit, sales tax is normally calculated from the taxable selling price of a transaction.
The business typically acts as the tax collector rather than bearing the economic cost when the tax is properly passed through to the customer, although businesses can bear tax economically in circumstances involving non-recoverable tax, incorrect collection, pricing constraints or purchases on which tax is not recoverable. Sales-tax systems differ considerably between jurisdictions concerning taxable products, services, rates, exemptions, registration thresholds, collection obligations and rules for transactions involving multiple jurisdictions.
A simplified sales-tax calculation is the taxable sale price multiplied by the applicable sales-tax rate. If a taxable item is sold for £100 and the hypothetical applicable rate is 10 percent, the customer-facing total would be £110 if the quoted £100 price is before tax. If the price is tax-inclusive, the tax must instead be extracted from the gross amount using the relevant fraction.
For example, where a hypothetical tax-inclusive price is £110 at 10 percent, the embedded tax is £10. Real systems can be more complicated because different products may have different rates, some sales may be exempt or excluded, and special rules can apply to shipping, discounts, bundled goods, returns and marketplace transactions. The seller's records therefore need to distinguish taxable sales from non-taxable sales and identify the correct rate.
Sales tax differs structurally from VAT. A traditional retail sales-tax system generally seeks to impose tax primarily on the final taxable sale to the consumer, whereas VAT is collected at multiple stages of the supply chain through output tax and recoverable input tax. Under a retail sales-tax model, a business purchasing goods for resale may provide appropriate exemption documentation so that tax is not charged on the business-to-business purchase, with tax instead collected when the goods are sold to the final customer. This design reduces cascading where correctly administered, but it requires accurate classification of customers, products and exemptions. VAT achieves a similar economic objective through a credit mechanism in which businesses generally charge output VAT and recover qualifying input VAT.
Sales-tax systems are strongly affected by jurisdictional boundaries. In federal or decentralised countries, states, provinces, cities or other local authorities may impose separate rates or rules. A seller may therefore need to determine whether it has a sufficient taxable presence or other collection obligation in a particular jurisdiction. E-commerce has made these issues more significant because a business can sell remotely to customers in many places without traditional physical stores.
Modern sales-tax regimes may use economic-nexus thresholds, marketplace-facilitator rules, destination-based sourcing and registration requirements. The exact legal test varies by jurisdiction, so businesses selling across borders or administrative regions must establish where tax must be collected rather than assuming that the rate of their home location applies to every transaction.
Exemptions and exclusions are important components of sales tax. Some jurisdictions exempt particular categories of food, medicine, education, financial services, essential goods or other transactions, while others use reduced rates or specific exemptions for resale, manufacturing or certain institutional purchasers. An exemption certificate or resale certificate may allow an eligible business customer to purchase without sales tax because the tax is intended to arise at a later taxable sale.
A seller must normally retain evidence supporting an exemption because improperly treating a taxable sale as exempt can leave the seller liable for uncollected tax. Taxability can also depend on whether a transaction is a sale of goods, a service, software, digital content, bundled products or a mixed transaction.
Sales tax creates important accounting and operational requirements. Sales tax collected from customers is generally recorded separately from sales revenue because the amount represents an obligation to the tax authority rather than income belonging to the business. A typical accounting system therefore records the taxable sale, records the corresponding sales-tax liability, and later reduces that liability when the tax is remitted. Returns require reconciliation between taxable sales in the accounting system, tax collected, adjustments, exemptions and amounts previously paid. Errors can occur when point-of-sale systems use outdated rates, when tax-inclusive and tax-exclusive prices are confused, when returns are not matched correctly, or when online sales are assigned to the wrong jurisdiction.
Sales tax is economically intended to tax consumption, although its incidence can be shared between consumers and businesses depending on market conditions. The statutory taxpayer or collector and the person who ultimately bears the economic burden are therefore not necessarily the same. Businesses may need to register once turnover or nexus reaches a statutory threshold, file periodic returns, collect the correct amount, issue compliant invoices or receipts, maintain records and remit the tax on schedule.
Failure to collect or remit tax can create assessments, interest and penalties. Conversely, collecting excessive tax or applying the wrong rate can create customer refunds and compliance problems. Sales tax should therefore be treated as a controlled transactional process rather than simply an additional percentage added manually to invoices.
Sales tax remains particularly relevant in jurisdictions that have not adopted a broad VAT or GST system. Its terminology can be confusing because some countries use the expression sales tax for taxes that have different legal designs, while other countries use VAT or GST for broad consumption taxes. A business researching sales tax must therefore identify the precise jurisdiction and statutory regime.
Important concepts include taxable sale, tax rate, exemption, resale, nexus, destination sourcing, marketplace facilitator, tax-inclusive pricing, tax-exclusive pricing, registration and remittance. The central principle is that sales tax generally attaches to defined taxable transactions and is collected from customers under statutory rules, rather than being a direct tax on the business's accounting profit.
