Rates are set by fiscal year, effective October 1 each year. Find current rates in the continental United States ("CONUS Rates").
Retirement plans must file certain forms and reports with the IRS and the Department of Labor and send out notices to plan participants and certain others. Different reporting and disclosure requirements apply depending on the type of plan and the plan’s circumstances.
These PDF charts summarize the reporting and disclosure requirements:
Form 5500 Corner - annual reports of a retirement plan:
Form 5330 Corner - excise tax returns
Form 8955-SSA Resources - reports on deferred vested benefits
Form 8822-B (PDF) to report a change in identity of a plan's responsible party
All retirement plan forms and publications
IRS Filing Notices for Form 5500, 5558 or 5500-EZ