Managing a retirement plan requires staying ahead of critical deadlines to ensure compliance with IRS and Department of Labor (DOL) regulations. As a plan sponsor, missing key filing or disclosure deadlines could result in penalties, additional taxes, or complications for your organization and plan participants.
To help keep you on track, we’ve outlined essential deadlines for the 2025 calendar year, covering compliance testing, participant disclosures, tax filings, and contribution deadlines. This calendar is designed for plans operating on a calendar-year basis. If any deadline falls on a weekend or federal holiday, the due date generally shifts to the next business day.
Q1: Setting the Stage for Compliance
Key Deadlines & Actions (January – March):
January 1 – Long-term, part-time employees are eligible to participate in the plan. Eligible employees include those with 2 consecutive years with 500+ hours of service per year.
January 15 – Review prior year census data.
January 31 – Deadline: Sending IRS forms to participants 1099-R for participants who received distributions from the plan in the previous year as well as Forms W-2, 945, 1099-NEC, and 1099-MISC.
February 15 – Review compliance testing results.
February 28 – Deadline: Filing Form 1099-R on paper with IRS to report distributions made in previous year. Deadline for electronic filing is March 31.
March 15
Deadline: ADP/ACP test corrective distributions to avoid 10% excise tax*
Note: A special deadline may apply to plans that satisfy the requirements of an eligible automatic contribution arrangement (EACA). See “June."
Deadline: Filing partnership tax returns and contribution deadline for deductibility (without extension) for companies operating on calendar-year fiscal year.*
Deadline: Requesting automatic extension to September 15 for partnership tax returns.*
March 31 – Deadline: Electronic filing of Form 1099-R to report distributions made in previous year (without extension).
Q2: Tax Filings and Compliance Testing
Key Deadlines & Actions (April – June):
April 1 – Deadline: The first required minimum distribution (RMD) is owed to participants who have reached age 73 or retired (whichever happened later) in the previous year.
April 15
Deadline: Processing corrective distributions for participants whose 401(k) deferrals exceed the annual 401(k) deferral limit under IRC Section 402(g).
Deadline: Filing individual and corporation tax returns.
Deadline: Contribution deadline for deductibility for self-employed individuals (without extension).
Deadline: Requesting automatic extension to October 15 for individual and corporate tax returns.
May 31 – Deadline: Filing HSA contributions and participant statements if applicable, review instructions for Forms 1099-SA and 5498-SA.*
June 30 – Deadline: Processing corrective distributions for failed ADP/ACP test from plan with EACA without 10% excise tax (if applicable).
Q3: Mid-Year Compliance Requirements
Key Deadlines & Actions (July – September):
July 29 – Deadline: Sending Summary of Material Modification (SMM) (210 days after end of plan year in which the amendment was adopted).
July 31
Deadline: Filing Form 5500 (without extension).
Deadline: Filing Form 5558 to request automatic extension of time to file Form 5500 (to October 15).
Deadline: Filing Form 5330 Return of Excise Taxes Related to Employee Benefit Plans, this is used to report and pay excise taxes on prohibited transactions and excess contributions that occurred in prior year.
September 15
Extended deadline: Filing tax returns for partnerships.
Extended deadline: Contribution deadline for deductibility for calendar-year partnerships and S-corporations.
September 30 – Deadline: Distributing Summary Annual Report (SAR) to participants, unless deadline for Form 5500 was extended, then two months after due date for Form 5500 (December 15).
Q4: Year-End Compliance & 2026 Planning
Key Deadlines & Actions (October – December):
October 1 – Deadline: Establish a new safe harbor plan for the current year.
October 15
Extended deadline: Filing Form 5500.
Extended deadline: Individual and/or corporate tax returns and final contribution deadline for deductibility.
Deadline: Adopting a retroactive amendment to correct minimum coverage or nondiscrimination requirements (IRC Sections 410(b) & 401(a)(4)).
December 1
Deadline: Sending annual 401(k) and safe harbor match notice.
Deadline: Establish a new safe harbor plan for the upcoming year.
Deadline: Sending annual QDIA, qualified default investment alternative notice.
Deadline: Sending annual automatic contribution arrangement notice (ACA).
December 15 – Extended deadline: Distributing SAR to participants.
December 31
Deadline: Processing corrective distributions for failed ADP/ACP test with 10% excise tax.
Deadline: Correcting a failed ADP/ACP test with qualified nonelective contributions (QNECs).
Deadline: Converting existing 401(k) plan to safe harbor non-elective design for current plan year.
Deadline: Amendment to remove or convert to safe harbor status for next plan year.
Deadline: Amending plan for discretionary changes implemented during plan year (certain exceptions apply).
Deadline: RMDs due under IRC Section 401(a)(9).
Stay on Track with 2025 Compliance Deadlines
Navigating retirement plan compliance involves staying informed and proactively managing key filings, corrective distributions, and participant notifications. Keeping up with these deadlines can help your plan stay aligned with regulatory expectations and avoid unnecessary penalties.
Serving as a plan sponsor comes with important fiduciary responsibilities, and compliance with ERISA regulations helps support both employees' retirement savings and your organization’s financial well-being. If you're uncertain whether your plan is meeting compliance obligations, reviewing your processes and seeking guidance can provide added clarity.
How Spectrum Can Help
Spectrum Investment Advisors provides retirement plan consulting designed to help plan sponsors manage fiduciary responsibilities, stay informed about compliance requirements, and support employees in their financial journeys. Our team helps plan sponsors gain access to resources and guidance to help manage their retirement plans effectively.
If you have questions, contact us today.
*The deadlines in this calendar are for plans with calendar-year plan years. If the filing deadline falls on a Saturday, Sunday, or legal holiday, the DOL provides that filing dates are delayed until the next business day. This calendar is intended to provide plan sponsors with a list of notable deadlines and is not a substitute for consultation with ERISA counsel, and in no way represents legal advice.