The research question
A supplier may cite inflation when requesting a higher price, a larger deposit, or shorter payment terms. That explanation can be reasonable, but a national headline does not show how much the supplier's own costs changed. A structured review separates broad price conditions from the materials, contracts, and timing relevant to your purchase.
Identify the price measure being quoted
Vietnam's consumer price index tracks a representative basket of household goods and services. It is not a direct measure of every manufacturer's input costs. The NSO also distinguishes producer and production-input price measures. Choose a measure that relates to the cost claim rather than applying consumer inflation mechanically to an industrial contract. NSO price definitions
Check the comparison basis. Month-on-month, year-on-year, and period-average movements answer different questions. The NSO explains these distinctions in its CPI methodology. Record the supplier's reference period and compare it with the date of the original quotation; a cumulative increase since last year is not necessarily an additional increase since last month. NSO CPI measurement explanation
Ask for a cost bridge
Request a simple bridge from the old quoted price to the new one: key materials, energy, labour, freight, exchange-rate exposure, and other material changes. Ask which items are invoiced in foreign currency and which are purchased locally. The exercise should explain the proposed adjustment, not demand unrestricted access to commercially sensitive records unrelated to the order.
For example, suppose the supplier attributes a ten-percent price increase to one material. Ask what share that material represents in the supplied product, when the new purchase cost applies, and whether existing stock was acquired at the old cost. The relevant calculation depends on those facts. An input's percentage increase should not automatically become the same percentage increase in the entire finished product.
Separate price pressure from funding pressure
A request for a bigger deposit may reflect the timing of cash payments rather than a permanent rise in unit costs. Ask when suppliers must be paid, how long production takes, and when the customer balance becomes due. Compare the explanation with available financial statements and the transaction schedule. Keep this funding question separate from the evidence supporting a revised unit price.
Where feasible, test the explanation against independent quotations or relevant published series using comparable specifications and dates. A mismatch calls for clarification. It does not, by itself, prove deception: product quality, purchase volume, transport arrangements, and contract timing can produce different prices.
Document the decision and review point
Record which elements were substantiated, which remained estimates, and what assumptions your purchasing decision uses. If you agree a temporary adjustment, identify when the supporting evidence should be refreshed. A good review leaves a clear trail from the external price claim to the company's exposure and finally to your particular order, without turning a broad inflation indicator into a substitute for company research.
What to take away
- Consumer inflation and production costs are different measures.
- Connect the adjustment to the product's actual cost components.
- Separate changes in unit economics from changes in cash timing.