Mature markets push global debt to record near USD 346 trillion, says IIF

NEW YORK – Developed markets led a borrowing push that lifted global debt to near USD 346 trillion at the end of the third quarter, while a pending ruling on the legality of US tariffs could force even more US issuance, a banking trade group said.

The Institute of International Finance said total debt reached USD 345.7 trillion by the end of September, equivalent to about 310% of global GDP, a relatively steady ratio since mid-2022. A softer US greenback helped inflate the value of most local-currency liabilities when translated into dollar terms.

“Most of the overall rise came from mature markets, where debt accumulation has accelerated rapidly this year as key central banks ease policy,” said the report co-authored by Emre Tiftik, director of sustainability research at the IIF.

CHINA AND US DELIVER LARGEST INCREASES

Through September, debt increased by USD 26.4 trillion this year, some USD 675 billion per week. Last quarter, China and the United States again delivered the largest increases in government debt, followed by France, Italy and Brazil, according to the IIF.

Mature markets’ outstanding debt rose to a record USD 230.6 trillion, while emerging markets also hit a record above USD 115 trillion. Russia, Korea, Poland and Mexico posted some of the largest increases.

A newly highlighted risk comes from the pending US Supreme Court decision on the legality of tariffs imposed by the Trump administration earlier this year. The IIF warned that an adverse ruling could materially increase fiscal pressure on the US, likely pushing the Treasury to borrow even more.

Government borrowing remained the primary driver of the global increase.

“With budget deficits still elevated – and the impact of large fiscal stimulus packages set to kick off in 2026 in Japan, the US, Germany, and China – sovereigns are likely to continue adding to their debt burdens and interest expenses,” according to the IIF.

EM EUROBOND ISSUANCE REACHED RECORD HIGH

On the market side, emerging market sovereigns have leaned more heavily on international markets this year. EM eurobond issuance has reached a record high in 2025, aided by the weaker dollar and continued policy easing by major central banks.

EM sovereign issuance this year stood at USD 255.7 billion at the start of December, according to a JPMorgan tally, making 2025 the highest annual gross issuance, with EM investment grade taking USD 182.1 billion of the total. The Wall Street bank considers this year a “one-off”, however, and expects next year to show a dip in issuance.

Despite the large issuance, access remains sharply limited, especially for countries emerging from debt restructurings, the report noted.

Corporate debt is also rising. Non-financial corporate liabilities are now approaching USD 100 trillion, the report said, with borrowing accelerating in AI-linked and clean energy sectors. US AI-related bond issuance hit a record in 2025, and new debt has continued to flow, prompting some concerns in the US corporate bond market.

Global household debt rose to nearly USD 64 trillion, but its debt-to-GDP ratio fell to 57%, its lowest since 2015, as households slowed borrowing amid heightened uncertainty and persistent cost-of-living pressures.

Looking ahead, emerging markets face nearly USD 8 trillion in bond and loan redemptions in 2026, while mature markets are set to refinance over USD 16 trillion, raising the risk of funding strains if global conditions tighten, said the IIF.

(Reporting by Rodrigo Campos in New York; Editing by Alison Williams)