Belgian Borrowing Costs Hit 14-Year High

The Belgian state’s ten-year borrowing rate exceeded 3.8% on Tuesday, reaching 3.803% — its highest level since 2012, according to RTBF. The development signals mounting pressure on a country already grappling with one of the eurozone’s highest debt burdens and a budget deficit well above European limits.

A Steady Climb Since March

The latest milestone follows a steady upward trajectory that began earlier this year. On March 23, the Belgian ten-year rate first exceeded 3.7%, reaching its highest point since January 2012 at the time, as RTBF reported. The rise was initially triggered by the outbreak of war in the Middle East and the subsequent surge in oil prices, which reignited inflation fears among investors.

The trend has not been confined to Belgium. Across Europe, sovereign borrowing costs have climbed in tandem. The French ten-year rate surpassed 4% for the first time since June 2009 on July 23, while the German Bund exceeded 3%, reaching 3.20% — its highest level since 2011, as La Libre reported. Even the German Bund, traditionally the eurozone’s benchmark safe haven, has not escaped the upward pressure.

For Belgium, the current rate level marks a stark departure from the era of historically low borrowing costs. For nearly a decade, the Debt Agency was able to refinance at exceptionally favorable terms, sometimes borrowing at 50-year maturities with rates below 1%. As Jean Deboutte noted, “An interest rate of 3.40% for 10 years is really the historical average. It’s perhaps even less than the historical average for Belgium, but one cannot take that for granted.”

Why Rates Are Rising

Jean Deboutte, Director of the Federal Debt Agency, attributes the sustained increase to the deteriorating geopolitical outlook in the Middle East. “Investors now fear high inflation over the long term, as well as a firm reaction from central banks that will raise their key rates due to this inflation,” he told RTBF.

The Strait of Hormuz blockage has significantly worsened global economic prospects, pushing oil prices higher and stoking inflation concerns. Investors in sovereign debt demand higher yields to compensate for the erosion of purchasing power, driving rates upward across European markets. As La Libre noted in March, the surge in oil prices following the outbreak of war in the Middle East made investors fear a resurgence of inflation, leading them to demand higher interest rates on sovereign debt to compensate for the loss of value.

A Heavy Burden for Belgian Public Finances

High interest rates represent a significant problem for Belgium’s public finances, as they make new borrowing more expensive on financial markets. The stakes are considerable: Belgium’s federal debt reached 574.990 billion euros at the end of July 2026, up 7.37 billion euros from the end of June, according to figures from the Federal Debt Agency.

The country’s overall public debt is projected to reach 110.5% of GDP in 2026, up from 107.9% in 2025, and could rise further to 112.8% in 2027, according to European Commission spring forecasts. The budget deficit stood at 5.2% of GDP in 2025 — well above the EU’s 3% reference level.

Rising Interest Charges

The cost of servicing this debt is escalating rapidly. Interest charges on the federal debt reached 10.78 billion euros in 2025, representing 1.68% of GDP, up from 1.64% the previous year, as RTBF detailed in its coverage of the Federal Debt Agency’s annual report.

Finance Minister Jan Jambon (N-VA) was blunt about the implications. “That means nearly 11 billion euros that we will not be able to invest in society,” he said. “These billions go up in smoke every year.”

The trajectory is concerning. According to Federal Debt Agency figures cited by 21news.be, the annual interest charge on Belgian debt is projected to rise from 12.2 billion euros in 2026 to 20.9 billion euros by 2030 — an increase of over 70% in four years. As a percentage of GDP, this would rise from 1.9% to nearly 2.8%, levels not seen since the early 2000s.

The Snowball Effect Risk

The rising interest burden revives the specter of the “snowball effect” — a scenario in which interest costs grow faster than GDP growth, causing the debt-to-GDP ratio to spiral upward. Jean Deboutte has warned this could occur by 2031 if no significant budget corrections are implemented.

Alexandre De Geest, President of the Strategic Committee of the Treasury, has been equally forthright about Belgium’s fiscal position. “With a deficit of 5.2% of GDP last year and a debt ratio of 107.9% (+4%), Belgium occupies the bottom of the European rankings and has not so far made the efforts of other countries, particularly those of southern Europe: Italy and Greece and even more so Spain and Portugal,” he noted.

A Government Under Pressure

The “Arizona” coalition government, led by Prime Minister Bart De Wever, faces a formidable fiscal challenge. The Monitoring Committee has determined that 7.7 billion euros in additional structural measures are needed by 2029 to meet European fiscal trajectory requirements, as VBO-FEB reported. This represents an increase from the 6.7 billion euros projected in March, reflecting the impact of the Strait of Hormuz blockage on global economic prospects and delays in implementing several measures from the December budget agreement.

Without new measures, the deficit could reach 5.8% of GDP by 2029 — approximately 42.5 billion euros. “One thing is certain: the effort required will amount to at least 7 billion euros. It could be even more significant,” Finance Minister Jambon warned.

The 2026 financing plan of the Federal Debt Agency projects gross borrowing needs of 59.55 billion euros, including a federal budget deficit of 26.37 billion euros, approximately 28 billion euros in medium and long-term debt maturing, and 4.60 billion euros in pre-financing for bonds maturing from 2027. Belgium must still borrow more than 50 billion euros on the markets this year.

What to Watch For

The coming months will be critical for Belgium’s fiscal trajectory. The government’s budget negotiations, expected to continue through October, will determine whether the country can stabilize its debt path. Key indicators to monitor include the evolution of the budget deficit, the average cost of new borrowing, and economic growth.

If interest rates continue to rise while the deficit remains elevated, Belgium’s debt burden will become increasingly difficult to manage. The 3.8% threshold crossed this week is more than a symbolic milestone — it is a stark reminder that the era of cheap borrowing is over, and the bill for years of fiscal expansion is coming due.

For now, Belgium can still refinance its obligations on international markets. But as the Director of the Federal Debt Agency cautioned, the current rate environment “cannot be taken for granted.” The window for corrective action is narrowing, and the cost of inaction is rising with every basis point.