What Is OPEC+? It Made 48% of World Oil Liquids

OPEC+ is the Organization of the Petroleum Exporting Countries (OPEC) and its partner producers. In 2025, the countries in its agreement produced 50.6 million barrels a day of oil liquids, according to OPEC. Oil liquids are crude oil, natural gas liquids and the other liquid fuels OPEC counts in world supply. World production was 104.8 million barrels a day on the same measure, so the group made 48.3% of it. In the second quarter of 2026 the share was 44.2%.

This post explains who is in the group, how it sets output and whether its announcements move the oil price. We tested six production announcements since November 2016. In the five trading days after them, the price of West Texas Intermediate (WTI), the US benchmark crude, rose after four and fell after two. The changes ran from a fall of 20.0% to a rise of 12.5%.

OPEC is a permanent group of oil-exporting countries. Iran, Iraq, Kuwait, Saudi Arabia and Venezuela founded it in Baghdad on 10 to 14 September 1960.

The "plus" refers to producers outside OPEC. On 10 December 2016, ministers from OPEC met 11 named non-OPEC producers in Vienna and signed the Declaration of Cooperation. The 11 were Azerbaijan, Bahrain, Brunei, Equatorial Guinea, Kazakhstan, Malaysia, Mexico, Oman, Russia, Sudan and South Sudan. OPEC's own statements now use the name OPEC+ for the group.

OPEC's Monthly Oil Market Report for September 2026 gives the answer. World liquids production was 104.8 million barrels a day in 2025. The countries in the agreement produced 50.6 million, or 48.3%.

That total has two parts. Crude oil was 42.0 million, or 40.1% of world liquids. Natural gas liquids and other non-conventional liquids were 8.6 million, or 8.2%.

All other supply, including 2.5 million barrels a day of refinery processing gains, was 54.2 million, or 51.7%. The United States alone produced 22.2 million, or 21.2%. Every share uses world liquids as its base. Chart 1 shows the split.

The crude and natural gas liquids bars add to the group's 48.3%. The other 51.7% sits outside every OPEC+ meeting.

No. Chart 2 shows the group's crude output by period. It was 42.1 million barrels a day in 2023, 40.9 million in 2024 and 42.0 million in 2025.

Output in the first quarter of 2026 was 39.9 million, 2.1 million below the 2025 average. It then fell by a further 5.6 million in the second quarter, to 34.3 million. Output in August 2026 was 38.1 million.

Across all liquids, the group's share of world production fell from 48.3% in 2025 to 44.2% in the second quarter of 2026.

OPEC's report records the second-quarter fall. The monthly statements set no output change of that size.

Three bodies take part. The full OPEC and non-OPEC Ministerial Meeting sets the framework. The Joint Ministerial Monitoring Committee (JMMC), with eight members, reviews output every two months. The monthly group, with seven countries since 7 June 2026, meets every month and decides voluntary adjustments.

The 38th Ministerial Meeting, on 5 December 2024, agreed the overall production levels that run until 31 December 2026. The 42nd meeting is scheduled for 29 November 2026. The 41st meeting, in June 2026, affirmed the importance of completing an assessment of each member's maximum sustainable production capacity, to be used as the reference for 2027 baselines.

The JMMC members are Saudi Arabia, Russia, Iraq, Kuwait, Kazakhstan, Nigeria, Algeria and Venezuela. It reviews output against required production, the level each country has agreed to produce. Countries that produce above that level state an intention to compensate later. The group's statement of 7 June 2026 extended the compensation period to the end of December 2026.

The monthly group announces voluntary adjustments to required production. Cuts of 1.66 million barrels a day came in April 2023 and 2.2 million in November 2023. The group has since been returning part of the April 2023 volume in monthly steps.

The steps were 206 thousand barrels a day on 1 March and 5 April 2026, then 188 thousand on 7 June, 5 July and 2 August. Each step is under 4% of the 5.6 million fall.

We tested six announcements, listed in the table. For each, we took the last WTI close before the announcement date. We then measured the change over the next five trading days. We fixed this rule before looking at the results.

WTI spot price in dollars per barrel. The close before is the last close before the announcement date. Source: OPEC press releases; US Energy Information Administration, WTI spot price

The first announcement is the OPEC Conference decision of 30 November 2016. The price rose after four announcements and fell after two. Starting from the last close on or before the announcement day instead gives three rises and three falls. The direction is mixed under both rules.

A normal week gives a yardstick.

Across 2,470 five-day windows from 29 November 2016 to 26 October 2026, the price moved by 3.0% in the median week, up or down. Five of the six announcement weeks moved by more than that. Chart 3 shows the six changes. The largest rise was 12.5% and the largest fall was 20.0%.

The test cannot say that an announcement caused a move. Each week holds other news.

Six events are also too few to estimate an average effect.

Four limits show in OPEC's own documents.

First, the group covers part of the supply. All other supply, including refinery processing gains, made 51.7% of world liquids in 2025.

Second, the group has no enforcement tool in its statements beyond a compensation mechanism. The statements record an intention to compensate for any overproduced volume since January 2024.

Third, membership changes. The statements of 30 November 2025, 1 March 2026 and 5 April 2026 name eight countries in the monthly group, including the United Arab Emirates. The statement of 7 June 2026 and the four after it name seven, without the Emirates. The statements give no reason.

Fourth, the scheduled steps are small against the swings in output. The statements of 6 September and 4 October 2026 held required production unchanged for October and November.

Each monthly statement gives four items. These are the countries that took part, the adjustment in thousand barrels a day, the month it takes effect and the date of the next meeting. The seven countries next meet on 1 November 2026.

The country figures sit in the statement as an image. Our explainer on how the oil market works covers where the price comes from. Our guide to the oil and gas industry covers the producers.

OPEC+ countries made 48.3% of world oil liquids in 2025. Six announcements gave four price rises and two falls within a week, so the test shows no consistent direction from an announcement to the price.

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Good places to start on the website:

OPEC+ is OPEC's member countries plus the non-OPEC producers that signed the Declaration of Cooperation, among them Russia, Kazakhstan, Mexico and Oman. The monthly group that decides voluntary adjustments named seven countries from 7 June 2026: Saudi Arabia, Russia, Iraq, Kuwait, Kazakhstan, Algeria and Oman.

No. Russia is one of the 11 non-OPEC producers that signed the Declaration of Cooperation on 10 December 2016, so it belongs to OPEC+ but not to OPEC. Russia sits on the Joint Ministerial Monitoring Committee and in the seven-country monthly group that decides voluntary adjustments.

OPEC is the permanent group of oil-exporting countries founded in Baghdad in 1960. OPEC+ adds the non-OPEC producers that signed the Declaration of Cooperation in 2016. In 2025, the countries in that wider agreement made 48.3% of world oil liquids, which OPEC measures as crude, natural gas liquids and other liquid fuels.

The seven-country monthly group meets on 1 November 2026, according to its statement of 4 October 2026. The Joint Ministerial Monitoring Committee and the 42nd OPEC and non-OPEC Ministerial Meeting are both scheduled for 29 November 2026. OPEC announces any change in its press releases.

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