Key Highlights

● RBOB gasoline rose 3.01% to $3.18 a gallon in Friday's session.

● Gasoline is down 6.60% on the month but up 67.41% on the year.

● US gasoline stocks rose by about 3.9 million barrels to 209.2 million barrels.

● Gasoline Demand fell 624,000 barrels a day to 8.36 million barrels a day.

RBOB gasoline futures rose 3.01% to US$3.18 a gallon in Friday's session on 30 October, following crude higher as Iran tensions returned to the market. The move matters to refiners such as Phillips 66 (NYSE:PSX), for which gasoline is one of the main products and the crude-to-gasoline gap is the main driver of margins.

The gain of US$0.09 trims a weak spell: gasoline is down 1.04% on the week and 6.60% on the month, though it is still 85.76% higher since the start of the year and 67.41% above a year ago. The contract has been hovering near its lowest levels since late August, so Friday's bounce comes from a low base.

Crude Pulls, Inventories Push Back

Gasoline rose in step with crude on Friday, with WTI up 2.85% and Brent up 3.06%. The inventory data are working against that rise. A gasoline stock build and weaker demand explain why the monthly trend is still negative while crude has gained 12.93% over the same period. The market is balancing a geopolitical premium against a comfortable Supply picture.

The Inventory Surprise

The Energy Information Administration reported that US gasoline stocks rose by about 3.9 million barrels to 209.2 million barrels in the week ended 23 October, when analysts had expected a draw of 0.9 million. Gasoline supplied, a proxy for demand, also fell by 624,000 barrels a day to 8.36 million barrels a day.

Even so, inventories remain around 2% below their five-year seasonal average, which keeps the picture from turning clearly bearish. Refinery utilisation slipped 0.6 percentage points to 92.8%, and seasonal refinery maintenance and strong diesel production ahead of winter could limit gasoline output.

Refiners Favour Diesel for Now

Refiners are prioritising higher-demand diesel, which explains why gasoline output is not the sole focus of the industry. Distillate stocks fell 1.5 million barrels to 102.8 million barrels and sit about 10% below the five-year average, so the Economics of a barrel of crude currently lean toward diesel. Heating oil rose 2.59% on Friday, a smaller gain than gasoline's.

Elsewhere, Middle East supply risks and Ukrainian strikes on Russian refineries continue to pose risks to global fuel flows. Europe plans to release 42 million barrels from strategic reserves over three months, largely diesel, and additional Chinese fuel-export quotas could increase global refined-product availability.

What It Means for Refiners and Retailers

Phillips 66 is a major US refiner. Gasoline is one of its main products, so its margins depend on gasoline prices relative to crude and on its product mix. Valero Energy (NYSE:VLO) is another large refiner and reported third-quarter net profit of US$6.828 billion and refining operating profit of US$8.782 billion on 22 October. A rise in crude that outpaces gasoline narrows refining margins, while a rise in gasoline that outpaces crude widens them. On Friday gasoline's 3.01% gain was slightly ahead of crude's 2.85%.

Retailers sit at the other end. Casey's General Stores (NASDAQ:CASY) sells fuel at retail, where margins per gallon often widen when wholesale prices fall and narrow when they rise, though competition limits this. Friday's rise in wholesale gasoline is the kind of move that tests those margins.

Gasoline Watch: Stocks, Refiner Results and the Midterms

The next weekly EIA petroleum report on Wednesday will show whether gasoline stocks build again and how demand holds. Refiners' quarterly results will show how margins held up, and the 3 November midterm elections remain the political date that reports link to possible military decisions on Iran.

Gasoline could rise if crude climbs on a failure of talks or further attacks, if refinery outages cut output or if inventories draw. It could ease if talks revive, if crude falls or if stocks keep building. Autumn typically brings lower driving demand than summer, which adds to the pull on prices.