The Cascade That Value Added Tax Was Built to Stop

Every consumption tax faces the same design problem: goods pass through several hands before anyone consumes them, and a tax charged at each handover accumulates. Value added tax, and the goods and services taxes modelled on it, exist as the answer to that problem. Maurice Lauré introduced the first full version in France in 1954, and the OECD now counts systems of this kind in more than 170 countries.

Seeing why the design was necessary takes one worked example.

The cascade, and the credit that removes it

Three independent firms. A supplier produces raw material worth 100. A manufacturer turns it into a product, adding 50 of value. A retailer sells it on, adding another 50. The value created along the chain totals 200. Tax is 10%, charged on every sale, with no relief anywhere.

The supplier invoices 100 plus 10 tax, so 110 leaves the manufacturer's account. The manufacturer's cost is that full 110 — the tax is a cost like any other — and adding 50 of margin brings its net price to 160. Ten percent on that is 16, so the retailer pays 176. The retailer adds 50, making 226 net, and charges 22.60 of tax. The consumer pays 248.60.

Total tax collected: 10 plus 16 plus 22.60, which is 48.60. On a value chain of 200 that is an effective rate of 24.3%, from a headline rate of 10%. The extra 28.60 is tax charged on tax.

Now change one thing. Suppose a single vertically integrated firm performs all three stages in house. There is one taxable sale, at 200 net, and the consumer pays 220. Identical work, identical value created, 28.60 less on the shelf price. A turnover tax quietly pays companies to merge, and it penalises long specialised supply chains for being long and specialised. That distortion, not the revenue, is what made the design untenable.

The fix is to let each business reclaim the tax it paid on its own purchases, so tax is remitted only on the value that business actually added.

The supplier charges 10 and remits 10. The manufacturer charges 15 on its 150 net price, claims back the 10 it paid, and remits 5. The retailer charges 20 on 200, claims back 15, and remits 5. The consumer pays 220 and the government collects 10 plus 5 plus 5, which is 20 — exactly ten percent of 200, and exactly what the integrated firm paid. The chain's length no longer affects the outcome.

That mechanism has a second effect the revenue authorities care about more than the neutrality. Because each business claims a credit only by producing its supplier's invoice, every firm has a direct financial interest in its suppliers reporting their sales properly. The tax largely audits itself, which is why the whole structure is often called the invoice-credit method.

Zero-rated and exempt are not synonyms

This is the distinction that catches people, and it only makes sense once the credit mechanism is clear.

A zero-rated supply is taxable at a rate of zero. The seller charges nothing on the sale but keeps the right to reclaim tax paid on inputs. Nothing sticks. Exports are usually zero-rated, because a destination-based tax belongs to the country where consumption happens, and the exporter should leave the system whole.

An exempt supply is outside the tax altogether. No tax is charged and no input credit may be claimed. A business making exempt supplies bought inputs of 100 plus 10 of tax, cannot recover that 10, and carries it as a cost — which means it goes into the price. Exempt does not mean untaxed. It means the tax is buried where nobody sees it and no consumer can identify it.

Both descriptions sound like relief. Only one of them actually is.

Where the arithmetic ends

Adding tax to a net price, or pulling it out of a gross one, is the easy half of this and our GST calculator will do it. What that page cannot tell you is what you owe, because the number that leaves your bank account is output tax less input credit, and the credit depends on your purchase records, on your suppliers filing correctly, and on which of your inputs are eligible at all.

Treat the calculator as an invoicing aid. For a single-rate value added tax outside India use the VAT calculator, and for tax added at the register in the United States model, the sales tax calculator — which is a genuine retail sales tax, charged only at the last step, and the notable holdout from everything described above.