What happened
Oil recorded its biggest weekly gain since mid July, climbing close to 9 percent as US strikes on Iran resumed for the first time in roughly a month. Brent crude, the North Sea benchmark against which most of the worlds oil is priced, traded at 96.11 dollars a barrel on Tuesday morning, spiked to 99.38 dollars on Wednesday, and settled back to 96.90 dollars by Friday.
The daily swings tell the story better than the weekly total. A gain of more than three dollars in twenty four hours, followed by a partial retreat, is the signature of a market trading on headlines rather than on physical shortage. No barrels have actually stopped flowing. What has changed is the probability that they might.
Context matters for how much this hurts. Brent is now roughly 30 dollars a barrel higher than it was a year ago, which means the pressure on fuel and energy prices is not a single week phenomenon but a year long shift that households and businesses have been absorbing gradually.
The reason a regional conflict moves the global price is geography. A substantial share of the worlds seaborne crude passes through the Strait of Hormuz, the narrow waterway at the mouth of the Gulf. Traders do not need a blockade to bid the price up. They only need to believe one is now more plausible than it was last month.
Why it matters
Oil is the one commodity that touches almost every price in the economy. It moves goods to shops, powers farm machinery, heats buildings and forms the raw material for plastics and fertiliser. When crude rises, the effect does not stay in the energy column of the inflation basket. It leaks into food, clothing and services over the following months.
That is exactly the wrong development for central banks that are already wrestling with energy driven inflation. The Bank of England is watching a 13 percent rise in the domestic energy price cap feed through household bills, and higher crude adds a second layer through petrol, diesel and transport. It is the kind of inflation monetary policy cannot fix, only offset by squeezing demand elsewhere.
For companies, the impact is uneven and creates clear winners and losers. Airlines, hauliers, chemical makers and anyone running a delivery fleet see costs rise immediately. Oil producers and oilfield services firms see profits jump. That divergence is a large part of why the FTSE 100, with its heavy weighting in energy, has behaved differently from technology heavy US indices this year.
There is a wider fragility here too. A world where oil moves 9 percent on renewed conflict is a world where the energy supply chain has little slack. Spare production capacity is concentrated in a small number of countries, which means the market has limited ability to absorb a genuine disruption without a much larger price spike.
Explained simply
The oil market prices fear long before it prices shortage. It behaves like travel insurance sold on the morning of a storm warning: nothing has been damaged yet, but the premium has already jumped, because everyone can see the clouds.
Oil is bought and sold mostly through futures contracts, which are agreements to buy a barrel at a set price on a future date. Airlines, refiners and manufacturers use them to lock in costs and protect themselves. Traders use them to bet on direction. The price you see quoted is the price of that promise, not the price of a barrel sitting in a tank today.
Because those contracts are about the future, they respond to anything that changes the odds of future supply. A missile strike near a shipping lane does not remove a single barrel from the market, but it raises the chance that barrels will be missing in three months. Buyers move to secure supply early, sellers demand more, and the price rises before anything physical has happened.
The reason a small percentage of world supply matters so much is that oil demand is stubborn in the short term. You cannot easily drive less next week or heat your home less because the price moved. When demand barely responds to price, even a small shortfall in supply requires a large price move to balance the market. That inelasticity is why oil is so violent compared with other commodities.
Then the price travels down the chain. Crude goes to a refinery, becomes petrol and diesel, moves to a forecourt, and reaches you. In the UK that journey typically takes two to six weeks, which is why the pump price always seems to lag the news, and why forecourts are accused of raising prices faster than they cut them.
What it means for you
The most direct effect is at the pump. As a rule of thumb, a sustained ten dollar move in Brent translates into roughly 5 to 7 pence a litre on UK petrol, though tax and retailer margins blur the relationship. On a 55 litre tank that is around 3 pounds each fill, and for a household driving 10,000 miles a year it adds up to somewhere near 100 pounds annually.
The indirect effect is larger but slower. Higher diesel costs raise the price of moving everything, so supermarket prices, delivery charges and tradesperson call out fees all drift upwards over the following months. UK food inflation had fallen to 1.3 percent in July, its lowest since August 2024, and sustained expensive crude is the most likely thing to reverse that improvement.
For investors, check what you already own before doing anything. A FTSE 100 tracker in your ISA or pension already gives you meaningful exposure to large energy companies, which act as a partial hedge, rising when fuel costs rise. Buying an additional energy fund after a 9 percent weekly move is usually paying up for a hedge you already hold.
Practically, this is a good week for the dull savings. Use a supermarket loyalty scheme or a fuel discount card, keep tyres properly inflated, and if you are choosing a new energy tariff, remember that gas and electricity prices in the UK are heavily influenced by international fuel markets. Fixing a tariff while crude is rising has historically been a reasonable hedge, provided the fixed price is close to the current cap.
The bigger picture
Every major oil shock of the past fifty years has followed the same rhythm: a geopolitical trigger, a rapid price spike, a period of demand destruction as households and businesses cut back, then a slow fall as supply responds. The 1973 embargo, the 1979 revolution, the 1990 invasion of Kuwait and the 2022 invasion of Ukraine all followed that pattern with different details.
What differs now is the transition. Electric vehicles, heat pumps and renewables are slowly weakening the link between oil and economic activity, which should make future shocks less painful. But the transition is far from complete, and in the meantime underinvestment in new production has left the market with a thinner cushion than it had in the past.
Watch two things. First, whether the strikes continue or fade, since the price premium will unwind quickly if tensions cool. Second, whether producers respond by lifting output, which is the mechanism that historically caps a rally. If crude holds near 100 dollars into the autumn, expect it to show up in the inflation figures before Christmas.
