Portugal Faces Most Expensive Bond Auction in 12 Years as War-Driven Inflation Reshapes Sovereign Debt Market

Portugal’s treasury agency IGCP is set to hold a double bond auction on Wednesday morning that will mark the most expensive regular issuance of 10-year government debt in over a decade. With 10-year yields trading at 3.53 per cent on the secondary market, the auction is expected to price above the 3.59 per cent paid on 23 April 2014 — when Portugal was still under troika supervision.

The IGCP will offer between EUR 1.25 billion and EUR 1.5 billion across 10-year and 14-year maturities, in what economists describe as a stark illustration of how the Middle East conflict has reshaped the eurozone’s sovereign debt landscape.

A 39-basis-point jump in under two months

At the last comparable 10-year auction on 11 February, Portugal issued EUR 673 million at an average yield of 3.142 per cent. Wednesday’s expected rate of around 3.53 per cent represents a 39-basis-point increase in less than two months — a pace of repricing that reflects the market’s reassessment of inflation expectations and ECB policy since the US-Israel military operations against Iran began on 28 February.

The 14-year tranche tells a similar story. With that benchmark trading at 3.83 per cent, Portugal would need to go back to September 2014 to find a higher rate for debt of comparable maturity.

Not just Portugal — a eurozone-wide phenomenon

The repricing is not unique to Lisbon. Since 27 February, the day before the conflict escalated, 10-year yields have risen sharply across the currency bloc. German Bund yields have climbed from 2.65 per cent to 3.1 per cent — their highest since June 2011. France’s 10-year yield has surged 57 basis points to nearly 3.8 per cent, the highest since 2009. Spain sits at 3.58 per cent and Italy at 3.99 per cent.

“The justification is the expectation of higher inflation resulting from the oil shock, which the market expects could result in a more restrictive monetary policy,” said Filipe Garcia, president of IMF – Informação de Mercados Financeiros. Pedro Brinca, professor at Nova SBE, pointed to “inflation expectations that are unanchored from the ECB’s 2 per cent target” and a “brutal increase in uncertainty, for which investors demand a higher return.”

Portugal’s short-term risk premium doubled in five days

The impact has been particularly acute at the short end of the curve. Between 27 February and 6 March, the spread on Portugal’s 2-year bonds versus the German equivalent more than doubled — a 119 per cent increase in just five days, the largest in the entire eurozone. Economists attribute this to a near-instantaneous repricing of ECB rate expectations, which swung from anticipated cuts to a projected 25-basis-point hike.

A cushion, but not a shield

There is a silver lining. The IGCP had front-loaded its borrowing programme, completing 35 per cent of its annual target by the end of March — well ahead of the calendar. That gives the treasury room to manage timing and volumes in future auctions.

“Portugal is well positioned, having secured 35 per cent of its financing in 25 per cent of the year, and has flexibility to manage future issuances,” Garcia noted, adding that “the average cost will rise, but without placing decisive pressure on public finances.”

Still, the maths is sobering. Portugal’s average issuance cost in 2026 stood at 3.1 per cent through March. With auctions now pricing above 3.5 per cent, that average will climb. And as Brinca warned, the country is simultaneously rolling over debt that was issued at near-zero rates: “We are doing rollover of debt that was at 0 per cent with debt at 3.5 per cent, plus an increase in the total stock.” The twin effects will add several tenths of a percentage point to the debt-servicing burden relative to GDP in the coming months.