At this time, Boldin does not have a feature for state tax-exempt interest.
The software computes and taxes interest annually for accounts with the Ordinary Income tax treatment. And, any interest will increase savings balance based upon the rate of return you enter.
If you want more granularity and to account for state tax free interest income, we generally recommend the following:
Navigate to My Plan > Assets and Debts
Create an Investment account
Select Ordinary Income Tax treatment
Set the rate of return to zero
Navigate to My Plan > Income > Pensions
Add a Pension to represent the monthly interest
Set the COLA to 0%
Select "No" for taxes
This method is for interest that is exempt at the state level but still taxable federally — most commonly US Treasuries and Treasury money-market funds.
If your bond is also exempt at the federal level (for example, an in-state municipal bond), use the Federal Tax Exempt Interest article instead, so the interest isn't taxed federally in error.