4 ms·Limited to 10k/yearby elijaht 4y agoLimited to 10k/yearceejayoz 4y ago$15k; you can buy $5k with your tax return. $30k if you've a spouse.JKCalhoun 4y agoHa ha, what tax return? Thanks, though. Setting up an account today.ceejayoz 4y agoIf you want, you can overpay taxes by $5k to get a refund to put into I Bonds.