Treasury Department sold a record nearly $1 billion of Series I bonds on Friday, the deadline to lock in higher rate

Investors purchased Series I bonds in record numbers from the U.S. Department of the Treasury on Friday, just beating a key deadline to lock in a historically high rate of return.

I bonds are a nearly risk-free asset tied to the rate of inflation. They’ve proven to be a bright spot for investors amid declines in the broad stock and bond markets this year.

Investors had a Friday deadline to buy I bonds and lock in a record-high 9.62% interest rate for six months. The rate reset Tuesday, falling to 6.89% — still the third-highest on record since the bonds debuted in 1998.

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The Treasury sold $979 million of I bonds before the deadline on Friday — nearly as much in one day as during the three years from 2018 to 2020, when investors bought slightly more than $1 billion, according to Treasury Department figures shared Tuesday. Investors opened 95,482 new accounts on Friday, also a record.

Investors purchased more than $3 billion of I bonds last week and almost $7 billion in October — which represent weekly and monthly records, too, according to initial estimates the Treasury Department provided on Monday.

Investors opened 359,822 new accounts last week and 731,336 new accounts during October.

TreasuryDirect.gov — the website where investors purchase I bonds — crashed on Friday as the volume swelled. TreasuryDirect became “one of the most visited websites in the federal government” in the final days of the 9.62% rate window, the Treasury Department said Friday. It typically hosts just a few thousand concurrent visitors.

I bond rates shift twice a year based on inflation.

There are two parts to the rate: a fixed rate, which stays the same after purchase, and a variable rate, which shifts twice per year based on inflation. The Treasury Department announces new rates every May and November.

Investors may lock in the new 6.89% rate for six months by purchasing I bonds any time before the end of April 2023.

You can purchase the assets online through TreasuryDirect, limited to $10,000 per calendar year for individuals. You can also use your federal tax refund to buy an extra $5,000 in paper I bonds.

The Treasury Department provided updated sales numbers after the story was published.