OECD raises 2026 growth to 2.9% on AI, lifts 2027 inflation to 3.6%

The OECD on Wednesday marked 2026 global growth up a tenth of a point, to 2.9%, and said the extra output is coming from AI-related investment even as a more persistent Middle East energy shock pushes G20 inflation out to 3.6% in 2027. In the same report it projected one more Federal Reserve increase in the fourth quarter, then a hold at 4% to 4.25% through next year.

Last year the world grew 3.4%. The first half of 2026 slowed to a 2.6% annualized pace, which was still stronger than the 2.0% the OECD had written in June. Secretary-General Mathias Cormann put the split in two sentences: almost two-thirds of the growth in global goods trade now comes from AI-related products, and “inflation is picking up again.” More than half of G20 countries, he said, now have inflation above their central bank’s target.

The September 14 oil path versus this morning's Hormuz talks

The 2027 easing in the baseline still requires energy prices to follow futures as of September 14: Brent averaging $105 a barrel and Dutch TTF gas €82 per megawatt hour in the fourth quarter of 2026, then $85 and €60 in 2027. Around 7:45 a.m. Eastern on Wednesday, Brent was $100.08 and WTI $90.60. The fourth-quarter oil print in the report is already above the live barrel.

The OECD’s estimates use information available through September 16. The Iranian seven-day reopening offer was reported September 22. This morning Trump says U.S. envoys met Iranian officials for three hours as Tehran offers a seven-day Hormuz reopening. The U.S. oil fund is down 11% in five sessions, with the strait still closed. The energy assumption predates the reopening talk.

The OECD listed a swift, full reopening of the strait as an upside. An illustrative simulation in the same report found that a 10% decline in oil and gas prices from the fourth quarter of 2026 onwards might raise 2027 global GDP growth by an additional 0.1 percentage point.

If energy prices stay high, the other side of the report is larger. The OECD’s illustrative downside stacks higher oil, gas and food prices, tighter financial conditions, and lower technical efficiency from energy shortages, supply-chain disruptions and adverse weather. Food prices are assumed 10% above baseline in 2027. Taken together, those shocks cut global growth by 0.7 percentage points in 2027 and raise global consumer-price inflation by 1.1 percentage points.

The financial channel is specified. For 2027 the OECD assumed oil and gas prices about 24% and 31% above baseline, global equity prices down 15%, investment risk premia up 35 basis points, and the term premium on long-term government bonds up 25 basis points. Disappointing AI earnings, it said, could slow investment in the sector, transmit into engineering and construction, and “deteriorate financial-market valuations.”

A holder of global stocks already has the AI concentration the OECD is using to hold 2026 up, and a much thinner energy sleeve. The iShares MSCI BACWI ETF BACWI, which tracks large- and mid-cap equities across developed and emerging markets, had 32.5% of assets in technology as of Tuesday and 4.1% in energy. Nvidia was 4.95% of the fund, Apple 4.78%, Microsoft 3.37%. The concentration holding 2026 up is the same book that takes the 15% equity drop in the downside.

On Tuesday the 10-year Treasury yield was 4.96% and the 30-year 5.29%, per the U.S. Treasury’s curve.

Those are the rates a 25-basis-point term-premium shock would be landing on, not a forecast that it will.

U.S. growth to 2.2%, India to 7.1%

The 0.1 percentage point global upgrade conceals a much larger re-ranking underneath. The OECD raised U.S. GDP growth to 2.2% in 2026 and 2.1% in 2027, from 2.0% and 1.8% in June, with “strong AI-related investment somewhat offset by a slowdown in consumer spending and real income growth.” India’s fiscal-year path, which the OECD dates from April, was lifted to 7.1% in FY2026-27 from 6.3%.

The OECD said euro-area demand strengthens once energy prices normalize and new defence spending gains pace.

The United States and India are where the OECD now finds the AI offset. Europe is where it finds the energy bill.

G20 inflation seen at 3.6% in 2027

The inflation revision is larger than the growth revision. G20 headline inflation is projected at 4.1% in 2026, up 0.1 percentage point from June, then 3.6% in 2027, up 0.5 percentage points from the 3.1% June path. That 2027 mark sits above the 3.4% the OECD recorded for 2025. Core inflation in the advanced economies is still seen easing, from 2.7% in 2026 to 2.5% in 2027.

The OECD blamed the near-term rise on commodity prices, “especially renewed energy-price increases,” and said moderating energy prices plus tighter policy should help inflation ease in 2027. Cormann was blunter about the gas market: the path the OECD now assumes is “around 60% higher” than the prolonged-disruption scenario it set out in June. He said the drag on growth should be greatest around the turn of the year, with inflation peaking in the fourth quarter of 2026.

On September 16 the Federal Reserve raised its target range by 25 basis points to 3.75% to 4.00% and said “inflation remains elevated.” The OECD’s baseline now adds one more increase in the fourth quarter and then holds the range at 4% to 4.25% through 2027, “reflecting continued inflationary pressures and solid projected GDP growth.” It also said further adjustments might be needed if price pressures broadened or growth weakened substantially. That is a two-way warning, not a call for cuts.

Whether 2027 inflation can fall from 4.1% to 3.6% still depends on energy prices following the September 14 curve lower. The strait is still closed.