Specific duty vs ad valorem: why some lines show Taka per tonne

Almost every line in the Bangladesh tariff expresses duty as a percentage. A handful do not. Those few lines are responsible for some of the most serious miscalculations in import costing, because the number looks like a percentage and is not one.

Two ways to charge duty

Ad valorem duty is a percentage of value. "25%" means 25 taka of duty for every 100 taka of assessable value. If the goods are worth more, the duty is more. This is how the overwhelming majority of the tariff works.

Specific duty is a fixed amount per unit of quantity. For example, a fixed number of taka per metric tonne, per litre, or per thousand units — regardless of what the goods cost. Import two tonnes and you pay twice the duty; whether those tonnes were cheap or expensive makes no difference.

The mistake, and why it is so costly

Consider a tariff line showing a customs duty figure of 3,000.

Read as a percentage, that is 3,000% — and on a consignment with an assessable value of 5,000,000 taka it implies 150,000,000 taka of duty. An absurd number, but people have produced it, because every other line they looked at that day was a percentage.

Read correctly as a specific duty of 3,000 taka per metric tonne, a 50-tonne consignment attracts 150,000 taka. The two answers differ by a factor of a thousand.

The error can run the other way too, and that direction is more dangerous commercially. An importer who sees "3,000" and assumes it must be a typo for 30% will understate the duty, quote a landed cost they cannot honour, and discover the problem only at assessment.

How to recognise one

Three reliable signals:

• No TTI figure. Lines carrying a specific duty show — instead of a Total Tax Incidence percentage on this site. This is the clearest signal, and it is deliberate. A total tax incidence expressed as a percentage of value is meaningless when the main duty does not depend on value.
• An implausibly large number in a duty column. Customs duty rates in Bangladesh sit in a recognisable band. A figure in the hundreds or thousands is almost never a percentage.
• The goods are bulk commodities sold by weight or volume — sugar, certain petroleum products, some steel, fertiliser, raw cotton.

On this site, pages for these lines suppress the worked example and show an explanation instead, precisely so that a percentage calculation is never displayed for a line where percentages do not apply.

Where they appear in the 2026-2027 tariff

Specific-duty lines are a small minority — 58 lines out of 7,469, well under one percent. But they cluster in chapters that ordinary importers deal with constantly:

Sugar and steel are the ones to watch. They are high-volume, they are traded by businesses of every size, and the quantities involved are large enough that a misreading is immediately expensive.

Why governments use specific duties

It is not arbitrary. Specific duties have properties that percentages lack.

They are resistant to undervaluation. If duty depends on declared price, there is an incentive to declare a low price; if it depends on weight, the incentive disappears, because weight is physically verifiable at the port.

They give predictable revenue on commodities whose world prices swing violently. Sugar and fuel prices can move by large fractions within a year, which would make percentage-based revenue impossible to budget.

They also provide stable protection to domestic producers. A percentage duty offers least protection exactly when it is needed most — when world prices collapse and cheap imports flood in. A fixed amount per tonne does not weaken as prices fall.

The trade-off is that specific duties are regressive against cheaper goods: the same taka-per-tonne is a much higher effective rate on a low-grade product than on a premium one. That is sometimes the intention.

Calculating one

The arithmetic is simple; the discipline is in the units.

1. Identify the unit of quantity in the tariff — metric tonne, kilogram, litre, thousand units. Do not assume.
2. Convert your consignment to that unit. A quantity in kilograms against a per-tonne rate is a factor-of-1,000 error waiting to happen.
3. Multiply quantity by the specific rate to get the duty.
4. Apply the remaining taxes according to their own bases. VAT and the other elements may still be value-based even where the customs duty is not, so the line is often a mixture, not purely specific.

That last point matters and is easy to miss. A specific-duty line is rarely specific in every column. Work through each element separately rather than reaching for a single percentage.

How rare they are, and where they sit

Specific duties are a small and deliberate corner of the Bangladesh tariff. Of 7,469 lines, 58 carry one — just over half of one percent. They are concentrated, not scattered:

Set out like this the logic is hard to miss. Sugar, steel, fertiliser, fuel, raw cotton, precious metals — these are bulk commodities traded by weight at volatile world prices. They are exactly the goods where an ad-valorem duty produces unstable revenue, and where declared values are hardest to verify.

The trade-off, stated honestly

A specific duty has one great advantage for the revenue authority and one corresponding disadvantage for the importer, and they are the same fact seen from two sides.

The duty does not move when the price moves. For the government that means predictable collection and no incentive for under-invoicing — understating the value of a tonne of sugar achieves nothing when the duty is charged per tonne.

For the importer it means the effective rate rises as prices fall. A duty of BDT 3,000 per tonne is 6% when sugar costs BDT 50,000 a tonne and 12% when it costs BDT 25,000. The protection tightens automatically in exactly the conditions that would otherwise make importing attractive.

This is not an accident or an oversight. A specific duty is a floor under the domestic price, and it is designed to hold when world prices collapse.

Why this site shows no percentage on these lines

A Total Tax Incidence figure is a percentage of assessable value. On a specific-duty line there is no percentage to state, because the duty is not a function of value — it is a function of weight or quantity.

Two consignments of the same goods, identical tonnage, bought at different prices, carry the same duty in taka but different percentages of their respective values. Printing a single TTI figure would be inventing a number that depends on information the tariff does not contain.

So these 58 lines show the rate as published — the amount per unit — and leave the percentage blank. That is a limitation of the arithmetic, not a gap in the data. To compute your own effective rate, divide the specific duty by your assessable value per unit, then run the percentage components on top in the ordinary way.

A hybrid, not a replacement

The most common misunderstanding is that a specific duty replaces the rest of the cascade. It does not. On the sugar lines, regulatory duty, VAT at 15% and Advance Tax at 7.5% all still apply, calculated on a base that includes the specific duty.

So a specific-duty line is really an ad-valorem structure with one fixed element at the front. Your landed-cost model needs both inputs — tonnage for the first component, value for everything after it — and a spreadsheet built around percentages alone will understate the total every time.

See one

Open 17011200 — other cane sugar. The page shows no TTI percentage and explains that the line carries a specific duty. Compare it with any ordinary line, such as 85171300 for smartphones, where a percentage TTI is shown and the worked example appears.

If you deal in sugar, steel, fertiliser or fuel, it is worth checking now whether the lines you use are on that list of 52 — before the question arises on a consignment that has already sailed.