https://www.thebalance.com/tax-advantages-of-series-i-saving...
1) No state tax on I-bonds
2) You can defer and pay tax on the interest only when you sell the bonds (which means you can time the sale to when you have lower income)
> or do they retain the 8% for however long you hold the bond?
No, the interest rate is updated every 6 months, see the sibling comment.
https://www.thebalance.com/tax-advantages-of-series-i-saving...
1) No state tax on I-bonds
2) You can defer and pay tax on the interest only when you sell the bonds (which means you can time the sale to when you have lower income)
> or do they retain the 8% for however long you hold the bond?
No, the interest rate is updated every 6 months, see the sibling comment.