you should have a 1099-DIV from the brokerage where you hold this position and should be reporting that
For the US Gov % refer to the ishares tax supplement below tho yes shows 100% US Gov Obligations. This would apply to the amount in your 1099-DIV Box 1a that comes from the TIP ETF, if you have other stuff in your account like a MM fund also paying dividends reported in Box 1a you have to calculate how much comes from TIP. Same process for MM funds or other holdings, if applicable get the US Gov % from the fund company.
It will be exempt from State tax but not Federal tax.
https://www.ishares.com/us/literature/tax-information/2025-ishares-us-government-source-income-infor...
