You don't need to create a separate 1099-INT for each bond....you create one for all $$/bonds of the same type i.e. all of the $$ in box 1 (&11) can be lumped together on a single 1099-INT, or box 3(&12) or box 8(&13).
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And you don't need to do individual 1099-INT forms at all, unless you have some accrued interest to report on any of the different bond-types (boxes 1vs3vs8).
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I don't know how Vanguard reports the accrued interest paid to the seller....You might have to call a Vanguard Rep with yoru list of purchases, and have them check it out for each bond.
(My Fidelity purchase confirmations shows the accrued interest paid out during the pruchase....right on the final confirmation form, that I download and save as a PDF ((and print out too)) a day or 2 after I execute the purchase)
____________*Answers are correct to the best of my knowledge when posted, but should not be considered to be legal or official tax advice.*
