What did SoftBank actually pay to raise $11.1 billion?

SoftBank paid up to 9.75% a year on its longest dollar bond. The size of the sale grabbed the headlines, but the rate is the number to read.

Masayoshi Son's company sold $10 billion of dollar bonds in three pieces. Then it added two euro pieces worth €500 million each. Reuters reports the sale is the largest high-yield corporate bond deal ever. Investors showed up. Satoru Aoyama, a senior director at Fitch Ratings, told Reuters he was "positively surprised by the market appetite."

Appetite has a price, though. Here is what the dollar bonds cost each year.

SoftBank's dollar bonds, September 2026
Amount Term Rate Interest per year
$1.0 billion 3.5 years 8.625% $86.25 million
$4.5 billion 5.5 years 9.25% $416.25 million
$4.5 billion 7.5 years 9.75% $438.75 million
$10.0 billion $941.25 million

The interest column is our own arithmetic from the coupons Reuters reported. The euro bonds pay 7.125% and 8%, which adds roughly €76 million more. That is close to $1 billion a year in interest before SoftBank repays a dollar of principal.

Why does 9.75% matter more than $11.1 billion?

Because a coupon is a fixed promise to pay, however the business is doing. Big AI numbers blur together. Interest does not.

Picture a controller reviewing a customer whose new loan carries a 9.75% rate. Nobody on that call asks whether the customer believes in its plan. They ask how much cash comes in each month to cover the payment. Bond investors are asking SoftBank the same question, and the price they charge is their answer.

The comparison with 2021 sharpens it. When SoftBank sold $7.3 billion of senior dollar and euro bonds that June, the yields ran from 2.125% to 5.25%. The new bonds run from 7.125% to 9.75%. The cost of insuring SoftBank's debt against default has also climbed. Reuters reports the five-year credit default swap spread topped 400 basis points this week, against about 280 in June.

None of this proves investors doubt the strategy. They lent $11.1 billion, after all. The fair reading is narrower: the money is available, but it is no longer cheap.

What is SoftBank borrowing for?

SoftBank is borrowing to own more of the AI supply chain, and OpenAI is the biggest piece.

Reuters says SoftBank has committed $64.6 billion to the ChatGPT maker and will hold roughly 13% of it by next week.

OpenAI is not the only bet. SoftBank agreed to buy ABB's robotics business in a $5.4 billion deal and has said it will acquire DigitalBridge, a digital infrastructure investor. It still owns the majority of Arm, the chip designer. It also runs SB Energy, its data center development company.

Put those pieces side by side and a pattern shows up. SoftBank is not just buying shares in AI companies. It is collecting the parts underneath them: models, chips, power, data centers and robots. That can be worth a great deal if the bet pays off. It also means the bills arrive on a schedule the bets do not control.

There is a plain difference between owning a company and lending to it. A shareholder can wait through a slow year. A bondholder cannot, because the coupon comes due on its date. That is why SoftBank's rate table reads differently from its list of investments. The investments show what SoftBank believes. The coupons show what it owes.

The maturities matter too. The dollar bonds come due in 3.5, 5.5 and 7.5 years. Every one of those dates falls well before a 20-year data center lease has run its course, so SoftBank will need fresh cash or new borrowing along the way. Refinancing is not a problem in itself. It does depend on lenders feeling as open in 2030 as they do today.