OPEC has published its Monthly Oil Market Report for September 2026, the cartel's regular assessment of crude supply, demand, and inventory trends that traders and refiners track for revisions to the global balance.

The report series, issued from OPEC's Vienna secretariat, is one of the two anchor monthly datasets for the crude market, alongside the International Energy Agency's Oil Market Report. Its September edition arrives at a point in the calendar when the organization's demand estimates for the coming year begin to take shape, and when supply forecasts for both OPEC and non-OPEC producers are updated against field-level data.

For downstream readers, the document's core value lies in its refinery tables. OPEC's monthly report tracks runs by region, estimated throughputs, and margins, giving refinery planners a benchmark for how cracking economics are holding up across Northwest Europe, the US Gulf Coast, and Singapore. The September report follows a summer season in which gasoline and middle-distillate spreads have been the swing variables for run rates globally.

For upstream readers, the report's secondary sources estimate OPEC crude production well by well-nation by nation — the numbers that feed into quota-compliance calculations. Any shift in the reported output of the core Gulf producers, or in the African members subject to lower baselines, feeds directly into how the market reads the group's next ministerial decision.

What the market is watching in this edition

First, the demand number. OPEC's growth forecasts for global oil demand have been the most closely parsed line in each 2026 report. Revisions in this edition — up or down — will set the starting point for how the balance looks heading into the fourth quarter.

Second, non-OPEC supply. US shale, Brazilian pre-salt, and Guyana's Stabroek block continue to drive the non-OPEC ledger. The September report's assessment of whether those supply additions are overshooting or undershooting earlier expectations will shape the call on OPEC crude for the remainder of the year.

Third, the compliance picture. Production from the voluntary-cut group versus targets is the number that determines whether the organization faces pressure to adjust policy at its upcoming meetings.

The report is available through OPEC's official channels, and the detailed tables repay close reading — the headline balance often moves less than the regional refinery runs and the stock data.

The watch item: the next OPEC and alliance of producing nations ministerial decisions, where the production-policy question lands squarely on the demand and supply numbers this report puts on the table. Traders will also be cross-checking the cartel's demand revisions against the IEA's own monthly assessment when it follows.