H.R.6321: To amend the Internal Revenue Code of 1986 to provide a refundable credit against income tax to assist individuals with high residential energy costs.

Home Energy Affordability Tax Relief Act of 2008 or the HEATR Act of 2008 - Amends the Internal Revenue Code to allow individual taxpayers an income-based refundable tax credit for residential energy costs. Limits such credit to the lesser of 33% of such costs or $500.