How Tariffs and Trade Policy Affect Markets
Who really pays a tariff is one of the genuinely contested questions in economics, and the answer shapes consumer prices, corporate margins, and how markets price uncertainty.
What a tariff actually does
A tariff is a tax on imported goods, levied at the border by the importing country. The legal payer is the importer of record — typically a domestic company bringing goods in — which pays the duty to its own customs authority, usually as a percentage of the shipment's declared value. The language around trade policy often implies that a foreign country writes a cheque; it does not. The tariff raises the landed cost of the imported good for the domestic firm buying it, and everything that follows — whether prices rise, whether margins compress, whether the buyer switches supplier — is a separate economic question from who is legally liable. Rules of origin, exemptions, and the availability of alternative suppliers determine how much of a headline tariff rate is actually paid, which is why effective and announced rates often differ.
Who bears the cost is genuinely contested
Research on the tariffs imposed from 2025 onward has tended to find that most of the cost fell on domestic importers, their customers, or both, rather than on foreign exporters. Analysis published by the Federal Reserve Bank of New York in early 2026 estimated roughly 90 percent of the burden falling on US firms and consumers, with foreign exporters absorbing about a tenth through lower export prices. Reviews published by the Peterson Institute during 2026 report similar magnitudes, while noting real disagreement about timing: some find close to complete pass-through within roughly seven months, others find it still incomplete six months in, with importers and retailers absorbing part of the cost in their margins. Estimates differ because of methodology, the period studied, currency moves, exemptions, and firms' choice to wait out legal uncertainty rather than reprice. The direction of the findings is reasonably consistent; the magnitudes are not. In practice the cost can land in several places:
- The foreign exporter, by cutting its price to keep the sale — research so far suggests this channel has been modest rather than dominant.
- The importing company's own margin, absorbed rather than passed on, at least initially.
- The distributor or retailer further down the chain, which may hold list prices steady to defend market share.
- The final consumer, through a higher shelf price.
- Nobody visibly, if the buyer switches supplier — though redesigning a supply chain is a real cost that never appears in a price index.
- Currency movements, which can offset part of a tariff if the exporter's currency weakens, or amplify it if it strengthens.
A shift in the price level is not the same as inflation
This is the distinction most often lost. If a tariff raises the price of affected goods once, measured inflation rises for roughly twelve months and then falls out of the annual comparison, even though prices remain permanently higher. That is a level effect. It becomes sustained inflation only if it feeds into expectations, wage bargaining, and the pricing of goods that were never tariffed — precisely the risk central bankers argue about when they debate whether to look through a tariff shock or respond to it. The available evidence suggests the effect can fade: research published by the Federal Reserve Bank of St. Louis in August 2026 found that the contribution of tariffs to US inflation had levelled off or slightly declined through the first half of 2026, alongside a fall in the effective tariff rate from a peak of roughly 11 percent in late 2025 to just under 7 percent by around May 2026, after court rulings and bilateral agreements.
A tariff changes the level of prices once; whether it changes the rate of inflation depends almost entirely on what everyone expects to happen next.
The last channel is the least visible and often the most consequential: uncertainty about trade policy is itself priced. When the rules could change within a quarter, firms defer capital spending, widen their earnings guidance ranges, dual-source components at higher cost, and hold more inventory than efficiency would justify. Each of those is a margin cost that shows up before any tariff is actually paid. Markets respond by demanding a higher risk premium from the most exposed sectors — import-heavy retailers, manufacturers with long cross-border supply chains, exporters vulnerable to retaliation — and implied volatility tends to rise around scheduled decisions and rulings. Plain Investor takes no position on whether any trade policy is desirable, which is a political judgement rather than an economic one; this article describes mechanisms and the range of published research. Figures cited reflect research available as of late September 2026.
This article is educational and general in nature. It isn’t personalized investment, tax, or legal advice — always weigh your own circumstances, or talk to a licensed professional, before making financial decisions.