If you are receiving a health insurance tax credit, then you applied through the Federally-facilitated Marketplace (Healthcare.gov) or a State-based Marketplace. You might remember including your household income in your application; it is your responsibility to report any changes in income that you may have during the year so that the tax credit can be adjusted if needed. At the end of the year when you file your taxes you don’t want to find yourself owing a fair amount of that tax credit back if your income went up. This can work both ways. If your income is less than you thought it would be, you may be given a larger tax credit of which you are not taking advantage. You may also need to verify the income that you have clammed to healthcare.gov . This can be done by mailing in the requested documents or by uploading them through your account. If you look back at your eligibility letter, dates on when this is due and a list of options for requested documents can be found there.