Treasury's Buyback Restarts at $6 Billion, September 2026

Treasury's first bigger long-end buyback runs today, September 10, 2026, and the cap on it is $6 billion, not the $4 billion floor Treasury announced on August 19. The story going around is that stablecoin issuers are the forced buyer paying for this, because the GENIUS Act makes them hold short-term Treasuries.

I went through the filings and that part isn't true yet. Treasury added $879 billion of bills in 12 months, against about $38 billion from the 2 biggest stablecoin issuers, and the larger of the 2 shrank in the first half of 2026. Bills are funding this buyback, not crypto.

What the Data Shows

Start with the operation itself. The one running today covers 40 eligible issues maturing between February 2037 and August 2046, with a maximum par amount of $6 billion and settlement on September 11, per the preliminary announcement TreasuryDirect posted on September 9. The August 19 press release promised only at least $4 billion per operation, up from a $2 billion cap, so the first one came in 50% above the floor. The buyback that ran on September 9 was a different one, a $12.5 billion cash management operation in the 1 month to 2 year bucket.

Yields haven't cooperated. The Fed's H.15 release dated September 9 puts the 10-year constant maturity yield at 4.80% on September 8 and the 30-year at 5.25%, against 4.65% and 5.19% on August 19, the day the bigger buybacks were announced. 3 weeks of anticipation moved the long end the wrong way.

The funding side is where the big number is. Treasury's Monthly Statement of the Public Debt puts bills outstanding at $7.248 trillion on August 31, 2026, up from $6.369 trillion a year earlier, and $557 billion of that $879 billion came in July and August alone. Total public debt barely moved over the same stretch, $40.10 trillion on September 3 and $40.08 trillion on September 8. Issue bills, keep the front end rolling, buy back the long paper the market keeps trying to hand back.

The stablecoin part is real law and small money. The GENIUS Act, Public Law 119-27, signed July 18, 2025, requires a permitted issuer to back its coins 1 to 1 with cash or Treasury bills maturing in 93 days or less, and it bars the issuer from paying holders any interest, so the structure is exactly as advertised. The size is not.

Tether's Q2 2026 attestation reports $183.62 billion of tokens issued on June 30, 2026, against $157.10 billion a year earlier and $186.45 billion at the end of December 2025, so USDT shrank over the first half of this year. Circle reported USDC at $73.3 billion on June 30, 2026, up 19% from a year earlier, which is roughly $12 billion of new demand.

Why It Matters for Your Portfolio

New supply is going into the part of the curve where the Fed sets the price, and the part where the auction sets the price is still repricing. The 30-year closed at 5.25% on September 8 and every September print in the H.15 table is 5.24% or higher, and that's the yield behind mortgages, long dated corporate paper, and every data center financed at a spread over Treasuries. If you're holding duration and waiting on a rescue at the long end, this is it, capped at $6 billion for one session.

What I'm Watching

Today's results print after the operation closes at 2:00 PM ET, and I want to see whether Treasury takes the whole $6 billion. The 10 to 20 year bucket filled its cap every time it ran this summer, $2 billion out of $7.4 billion offered on August 11 and $2 billion out of $16.3 billion on July 23. The offers are there; the question is what Treasury accepts.

Then the FOMC on September 15 and 16, and November 4, when Treasury says at the refunding what buyback sizes look like next quarter. If bills keep growing at August's pace, $259 billion in a month, and the 30-year still won't print under 5.20%, the buyer everybody is looking for isn't the one they're looking at.

Related Reading: Treasury's Buyback Bought 2 Days of Lower Yields in 2026 and The Dollar's Second Life Is Being Built On Chain Now

Howard is a full-time trader based in New Jersey with 13 years of experience across Forex, crypto, equities, and futures. He started Position Note to document his trades and analysis in public. All positions are disclosed. Nothing here is personalized investment advice.