Guidance published by IRS related to retirement plans.
Retirement plan guidance by type - October 2000 to date
Monthly weighted-average interest rates
Section 7520 tables for valuing annuities, life estates, remainders and reversions
Information relating to the Priority Guidance Plan, including links to both the current and prior versions, and news or notices about the Plan.
Text of revenue rulings, revenue procedures, and other technical items in advance of their Internal Revenue Bulletin publication date
The place to start for researching publicly accessible versions of the Internal Revenue Code, Treasury (Tax) Regulations, or other forms of official IRS tax guidance.