Berkshire Hathaway’s $359.2 billion cash and Treasury bill pile has yet to show a clear boost from higher U.S. rates, even after the Federal Reserve raised its benchmark by 0.25 percentage points to 3.75%-4.00% on September 16. According to BeInCrypto, interest, dividend and other investment income for the first half of 2026 came in slightly below the same period last year, despite the larger cash position.

The lag reflects the time it takes for older Treasury bills to mature and be reinvested at higher yields. Berkshire’s net earnings more than doubled to $35.8 billion, driven mainly by unrealized gains on stock holdings, while the Fed has signaled one more increase before year-end.