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U.S. Series I Savings Bonds are a unique investment because all interest is rolled into principal until redemption, and in most cases, all the compounded earnings are tax deferred until the I Bond is redeemed or matures.
A rather large tax bill is coming for investors in these early-year I Bonds. When the I Bonds are redeemed or mature, the entire amount of interest will be subject to federal income taxes in that year.
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