Sterling rarely drifts quietly. When it slides, the reaction splits in two: exporters call it a gift, shoppers call it a tax, and the FTSE 100 sometimes closes higher on the very day the news pages are full of gloom about prices. Both reactions can be correct, because the index and the economy are not the same thing. The question that actually pays is narrower — which companies are paid in dollars, and which ones pay in them?
Why the FTSE 100 is not the UK economy
A large share of FTSE 100 revenue is earned outside the UK, and much of it is invoiced in dollars. Think of a mining group selling iron ore to Asian steelmakers, an oil major whose barrels are priced in dollars, or a pharmaceutical company whose biggest market is the United States. Nothing about those businesses changes when sterling falls, but the numbers they report in pounds do. Overseas profit translated back at a weaker exchange rate is worth more, so reported revenue and earnings per share can rise without a single extra unit being sold.
Now look at the other side of the same coin. The UK runs a goods trade deficit, which means the country imports more in value than it sells abroad. Energy, food, machinery, components and finished consumer goods are typically priced in dollars or euros and settled in sterling. When the pound falls, the same barrel, container or pallet costs more to bring in. One currency move, two completely different effects — and the index only captures the flattering half.
This is also why the FTSE 250 deserves separate attention. It holds more domestically focused businesses: housebuilders, retailers, pubs, letting agents, support services. They earn in pounds and often buy in foreign currency, so a weak pound hurts rather than helps. It is not a clean split — plenty of mid-caps earn overseas too — but the broad direction is worth remembering before you assume a falling pound is good news for UK equities.
Who really gains from a weaker pound
The clearest beneficiaries tend to sit in sectors with high overseas revenue and low imported input costs: mining, oil and gas, pharmaceuticals, defence, parts of engineering, and consumer staples with heavy US exposure. For these businesses, sterling weakness is a tailwind to reported profit and, often, to the dividend that lands in a UK investor's account.
The benefit is not universal across the index, though. A company that sells in dollars but buys its components in dollars simply has a matched book — the currency move washes through. A company that reports in sterling but carries dollar borrowings can see its interest bill and its debt-to-earnings ratio move the wrong way.
A translation gain is not a verdict on the business
It is worth being blunt about this. A currency translation gain is an accounting effect, not evidence of improving demand, better pricing power or smarter management. It flatters headline earnings per share, which feeds into valuation multiples and can make a company look cheaper than it really is on underlying numbers. When sterling recovers, the effect reverses just as quietly.
The inflation channel: from import invoice to shop shelf
Currency weakness reaches consumers with a lag, and the lag is where most of the argument happens. An importer facing a higher sterling cost has three choices: absorb it into margin, find savings elsewhere, or pass it on. Most do a bit of each, in that order, which is why imported inflation arrives in stages rather than overnight.
Energy and food tend to transmit fastest, because they are commodity-linked and contract prices reset regularly. Manufactured goods move more slowly, especially where retailers hold stock bought at older exchange rates or where contracts are fixed for a season. Services inflation, by contrast, has little to do with the exchange rate at all — which is why a weak pound can push up goods prices while leaving the bigger domestic inflation picture untouched.
There is a circularity here that trips up tidy forecasts. A weaker pound adds to imported inflation, which complicates life for rate-setters and can mean interest rates stay higher for longer than markets expected. Higher rates, in turn, tend to support the currency. That loop is real but slow, and it is a reason to treat any single currency move as a tendency rather than a destination.
Consumer-facing shares feel it first
Companies that sell in pounds and buy in dollars carry the squeeze most visibly. Food producers, general retailers, airlines buying jet fuel priced in dollars, travel operators, restaurants and parts of the utility sector all sit in that group. Margins in food retail and general retail are thin, so a few percentage points on the cost of goods sold is enough to matter.
Pricing power is the dividing line. A branded business with loyal customers can push through an increase and keep volumes roughly intact. A commodity retailer cannot, and instead watches volumes fall as shoppers trade down. Discount chains sometimes pick up customers in that environment, but they face exactly the same import costs as everyone else — they are not immune, merely better placed.
- Cost currency: what share of the cost of goods sold is bought in dollars or euros?
- Revenue mix: how much of turnover comes from the UK versus overseas?
- Hedging: how far forward is currency risk hedged, and when does that cover roll off?
- Pricing: can the company raise prices without losing volume?
- Debt: are borrowings in sterling or foreign currency?
Where the signals show up in company accounts
- Read the segmental note in the annual report for revenue by geography. It tells you the real currency mix, not the listing address.
- Find the hedging paragraph in the financial instruments note. Look for how long cover runs and what proportion of exposure is protected.
- Check the borrowings note for the currency of debt and any foreign exchange losses booked through the income statement.
- Follow the pricing commentary on results calls. Management teams usually signal cost pressure well before it hits reported margins.
- Note the currency of the dividend. A payout declared in dollars is worth more in pounds when sterling is weak.
Reading the next sterling headline
Ask three questions before drawing conclusions. First, what actually moved? A pound that falls against a broadly strong dollar is a different story from one that falls against everything, and sterling's move against the euro matters at least as much for UK trade.
Second, who in your portfolio has the exposure? Most UK investors already hold unhedged overseas assets, which means a falling pound quietly boosts the sterling value of global funds. That is useful diversification, not a reason to add more risk on a currency view alone.
Third, is the move likely to stick? Currency forecasts are unreliable, and positioning a portfolio around a predicted exchange rate tends to disappoint. The more durable approach is to know your exposure, spread it sensibly and avoid confusing a translation gain with genuine business improvement.
Finally, a note on what this is: general information, not personal advice. If you are considering changes to a portfolio, savings or a mortgage in response to currency moves, a regulated adviser can look at your circumstances rather than the headline.
Photo: stux / Pixabay
