US companies issued $57 billion in convertible bonds in 2026 through the comparable period — the highest level on record for that stretch, according to Barclays Research — as AI infrastructure spending pulled a corner of the debt market back to volumes not seen since the early pandemic surge.

Total convertible bonds outstanding crossed $300 billion for the first time since COVID-19, per FactSet data published December 2025, with global issuance pace running at a 24-year high as of January 2026. By June 2026, market volume had reached its highest level since the pandemic's onset. Deals hit a five-year high as early as September 2025, meaning this cycle had been building for several quarters before it cleared the headline thresholds.

The Mechanics Driving the Trade

Convertible bonds occupy an unusual position in the capital structure: they pay a coupon like ordinary debt but include an embedded option allowing the holder to convert into equity at a preset price. For issuers, that equity optionality functions as a subsidy — companies can offer a meaningfully lower coupon than on straight debt because bondholders are partly compensated by the conversion feature. For CFOs deploying capital into long-horizon, high-volatility projects like AI datacenters or cloud buildouts, the lower cash interest burden matters.

The rate environment sharpens that calculus. After years of near-zero rates, the cost gap between convertible and straight high-grade or high-yield debt has widened enough that the equity dilution risk — the price issuers pay for the cheap coupon — becomes an acceptable trade-off, particularly for companies whose share prices have already been bid up on AI enthusiasm.

Alibaba's activity illustrates the pace. The company raised $5 billion via convertible bond in May 2024, followed by $1.5 billion through an exchangeable bond in July 2025, and then announced a $3.2 billion convertible offering in September 2025 specifically earmarked for cloud growth. Three distinct capital markets transactions in roughly 16 months, each tapping the same basic instrument. That cadence is less a sign of financial stress than of a company methodically matching long-dated asset spending to a financing form that minimizes near-term cash outflows.

Scale and Context

The $57 billion US figure for 2026 sits atop a trajectory that was already moving fast. LSEG data from April 2024 showed more than $20 billion issued in the US in Q1 2024 alone, with $26 billion globally in the same quarter. The subsequent acceleration — past $300 billion outstanding, past 24-year issuance pace records — reflects both the broadening of AI capex ambitions and the market's appetite to absorb paper at scale.

For context, convertible bond markets were largely dormant through much of the 2010s rate suppression era, when plain vanilla investment-grade debt was cheap enough that the complexity of a convertible offered little incremental benefit to issuers. The post-2022 rate reset changed that equation. Higher base rates mean higher coupons on straight debt, which makes the coupon subsidy embedded in a convertible structure more valuable. The reopening of this market, then, is partly a rate story and partly a technology capex story — the two arrived simultaneously.

The supply-demand dynamic also warrants attention. Convertible arbitrage funds — which buy the bonds and short the underlying equity to isolate the embedded option — provide a reliable bid, but their capacity is finite. The pace of issuance so far in 2026 will test whether that structural buyer base can absorb volume without demanding materially worse terms from issuers. If spread compression begins to show up in deal pricing, it would signal the arbitrage community is nearing saturation, and issuers may face less favorable structures.

The broader pattern is one of financing form following capex cycle. When a technology wave demands front-loaded capital expenditure against uncertain but potentially large equity upside, convertibles are a natural fit. The AI buildout has the right profile: capital-intensive now, with equity optionality that investors are willing to price generously. Whether the conversion premiums embedded in these bonds ultimately prove correct depends entirely on AI monetization timelines that remain genuinely unresolved. The bond market is pricing in optimism. The actual infrastructure still has to earn it.