US bond funds attract $625B in inflows through August, highest since 2010

Over the 12 months ending August 2026, US bond funds pulled in $625 billion in net inflows, the highest annual total since at least 2010. That’s a staggering amount of capital flowing into an asset class that, on paper, hasn’t exactly been rewarding its holders lately.

The iShares Core US Aggregate Bond ETF (AGG) dropped roughly 4% over the period, and the iShares 20+ Year Treasury Bond ETF (TLT) fell about 6.9%. Investors watched their bond holdings lose value and responded by… buying more bonds.

The numbers behind the rush

August alone was a monster month. Taxable-bond funds attracted $69 billion in new cash, according to Morningstar data. That marked the fourth straight month where inflows topped $60 billion, only the second time that’s happened on record. The first was the May-to-August stretch of 2020, when the world was still figuring out what a pandemic meant for portfolios.

Long-term US funds collectively gathered $100 billion in August inflows. Taxable bonds accounted for nearly 70% of that total, making fixed income the undisputed engine of fund flows.

Bond ETFs specifically recorded somewhere between $55 billion and $57 billion in August inflows, bringing their year-to-date haul to approximately $407 billion. Total US ETF flows hit around $180 billion for the month, meaning bond products claimed roughly a third of all ETF dollars.

The 10-year Treasury yield, as of mid-to-late September, sat at approximately 5%. That’s the highest it’s been since 2023 and, before that, 2007. For context, the 10-year spent most of the 2010s below 3%.

Short and sweet is the play

Not all bonds are getting equal love. Investors have shown a clear preference for the shallow end of the duration pool.

Ultrashort bond funds led all categories with $15 billion in August inflows. Short government funds posted their second-largest monthly intake ever recorded.