What state? Treasury interest on your tax refund is taxable. Its not the same kind of Treasury interest on. Savings Bonds and mutual funds.
Dud you get a 1099int or letter for it? What box is it in? Should be box 1.
Box 3 of Form 1099-INT shows the interest income you received from U.S. savings bonds, Treasury bills, Treasury notes, and Treasury bonds.
IRS interest is none of those.
