The OECD Says AI Is Holding the World Economy Together. It Doesn't Expect That to Last.

The global economy is holding up better than expected this year. The OECD's message on Wednesday was that the reasons it is holding up are wearing thin.

In its September interim economic outlook, the Paris-based Organisation for Economic Co-operation and Development raised its 2026 global growth forecast to 2.9%, from 2.8% in June — then trimmed 2027 to 3.0%, from 3.1%. Growth last year was 3.4%. And inflation, which the OECD had expected to keep easing, is running hotter: G20 inflation is now seen at 4.1% in 2026, up from 4.0% forecast in June, and 3.6% in 2027, up sharply from 3.1%.

The headline forecast is better. What's more interesting is the warning underneath it.

The resilience is real — and it's mostly AI

The single biggest reason the world economy is outperforming, in the OECD's telling, is artificial intelligence — or more precisely, the money being poured into it. Strong spending on AI infrastructure, from data centers to semiconductors, has been a key pillar of resilience this year, boosting growth in the United States and lifting technology exports from Japan and Korea.

In the US, the world's largest economy, growth is now seen at 2.2% this year and 2.1% in 2027 — both upgrades from June — as heavy AI-related investment offsets weaker consumer spending. US inflation is projected at 3.6% in 2026, easing to 2.6% in 2027, with tariffs and higher energy prices weighing on household purchasing power and business costs.

The Middle East energy shock, meanwhile, has been absorbed better than feared. The OECD says alternative supply routes, inventory drawdowns — including coordinated strategic-reserve releases — additional non-Gulf production, and weaker Chinese oil demand all cushioned the blow to global growth this year.

The buffers are being depleted

That cushion is the OECD's central warning. "Global growth has held up better than expected, but the buffers that absorbed the energy shock are being depleted," Secretary-General Mathias Cormann said. "Growth is weaker than last year and inflation is rising again."

The risks clouding the outlook are specific: fresh energy-market jitters, extreme weather tied to a strong El Niño, surging long-term government bond yields that tighten the fiscal screws on indebted governments, and — the one markets will fixate on — disappointing returns on AI investment.

That last risk carries a sting the OECD spelled out: AI investment is increasingly relying on external financing, which it said could amplify a market correction if the expected returns fail to materialize. The boom supporting 2026's growth is, in part, a leveraged bet.

The 2027 risk scenario

The OECD put numbers on what happens if those risks arrive together: global growth in 2027 would fall 0.7 percentage points short of the baseline, and global inflation would run 1.1 percentage points hotter. On a 3.0% baseline, that is the difference between a slow year and a genuinely bad one.

For central banks, the prescription is vigilance. The OECD said policymakers should keep inflation expectations firmly anchored and stand ready to adjust interest rates if price pressures broaden or growth falters — a two-sided warning that rate cuts are not the only direction of travel. It also urged governments to keep energy support measures targeted and temporary, and to put public finances on a sustainable path as rising sovereign yields raise borrowing costs.

The outlook at a glance

Global growth: 2.9% in 2026, 3.0% in 2027 (June: 2.8%, 3.1%). G20 inflation: 4.1% in 2026, 3.6% in 2027 (June: 4.0%, 3.1%). United States: 2.2%, then 2.1%. Euro zone: 1.0%, then 1.0%. China: 4.5%, then 4.2%. Japan: 0.8%, then 0.7%. Combined risk scenario for 2027: growth 0.7 points lower, inflation 1.1 points higher.

The regional map

The euro zone is the laggard among major economies: growth seen holding at just 1.0% in both 2026 and 2027, with higher energy prices and interest rates weighing on activity before new defense spending initiatives provide support. Euro zone inflation is forecast at 3.0% this year and 2.9% in 2027, driven partly by a jump in natural gas prices as European storage levels sit at 15-year lows heading into the winter heating period.

China's growth is expected to slow to 4.5% this year and 4.2% in 2027, unchanged from June, as Beijing's curbs on excess industrial capacity weigh on investment even as consumption faces a gradual pickup in inflation.

Japan is the outlier in the inflation story. Its economy is expected to grow just 0.8% in 2026 and 0.7% in 2027, but unlike other major economies, its inflation is seen accelerating — to 2.6% in 2027 from 1.8% this year — reflecting a tight labor market and strong wage growth.

Canada took the sharpest downgrade: 2026 growth cut to 0.9% from 1.2% in June, and 2027 lowered to 1.3% from 1.7%, on new US tariffs hitting Canadian exports.

What the OECD is really saying

Read as analysis rather than forecast — and the OECD invites that reading — the outlook rests on two load-bearing bets. The first is that AI investment keeps paying: the spending boom cushioning 2026 has to produce returns, because it is increasingly financed with other people's money. The second is that inflation expectations stay anchored while governments absorb higher borrowing costs and households absorb higher energy bills.

If either bet breaks, 2027 looks less like the 3.0% baseline and more like the risk scenario: growth 0.7 points lower, inflation 1.1 points higher. The OECD titled its outlook "Weathering Successive Shocks." Weathering, notably, is not the same as recovering.