IRS notices and forms can involve refund holds, balance-due bills, proposed adjustments, identity checks, collection action, transcript codes, or filing requirements. This resource center explains what common IRS letters, notices, forms, and account entries mean, which deadlines matter, and what to check before responding. Use these guides to compare a notice with your tax return, determine whether the IRS is requesting information or payment, and understand when appeal rights or collection deadlines may apply. Start with the notice number, letter number, form name, or transcript code shown on your document.