On September 18, 2026, the Pension Benefit Guaranty Corporation (PBGC) issued Technical Update 26-1, providing a temporary waiver from reporting requirements under ERISA regulation section 4043.23(a)(2) if a single-employer defined benefit (DB) plan covered by Title IV of ERISA experiences an attrition event. The waiver applies to active participant reduction attrition events for which the reporting deadline is on or after September 18, 2026.

What are PBGC reportable events?

ERISA Section 4043 requires plan administrators or contributing sponsors of single-employer DB plans to notify the PBGC when specified events occur that could signal increased risk to the plan or to the sponsor’s ability to maintain it. PBGC’s reportable event regulations describe which events trigger notice and what information must be provided. In most situations, PBGC Form 10 is used to notify the agency of the reportable event and is due within 30 days after the event takes place. In some cases, advance notice to PBGC may be required before the event occurs.

Reportable events that require reporting to PBGC include:

• Active participant reduction
• Failure to make required minimum funding payment
• Inability to pay benefits when due
• Distribution to a substantial owner
• Change in controlled group
• Liquidation
• Extraordinary dividend or stock redemption
• Transfer of benefit liabilities
• Application for minimum funding waiver
• Loan default
• Insolvency or similar settlement

Which reportable event is eligible for the temporary PBGC reportable event waiver?

There are two types of active participant reductions, which are described in the following bullets. The reportable event that is eligible for the temporary reporting waiver is an attrition event. Technical Update 26-1 does not waive reporting of single-cause events.

• Single-cause event. This is an event that causes more than 20% of the plan’s active participants to cease active status during the plan year, such as a reorganization or restructuring, business shutdown, mass layoff, natural disaster, or retirement incentive program.
• Attrition event. An attrition event occurs “at the end of the plan year if the sum of the number of active participants covered by the plan at the end of such plan year plus the number of individuals who ceased to be active participants during the same plan year that are reported to PBGC under [the single-cause event] section is less than 80% of the number of active participants at the beginning of such plan year.”¹

The regulation includes rules for determining who counts as an active participant, coordinates the analysis across controlled group employment changes, and disregards certain reductions already reportable under other ERISA cessation or withdrawal provisions. It also provides several examples to illustrate how the rules work. Reporting is generally not required for small plans (100 or fewer participants), plans whose contributing sponsors and top U.S. parent present a low default risk, plans that satisfy the well-funded safe harbor, certain events disclosed on a timely SEC Form 8-K by a public company sponsor or parent, and active participant reduction events already covered by other reportable events.

We reviewed the rules for reporting an active participant reduction prior to Technical Update 26-1 here.

Temporary waiver: After reviewing recent reportable event filings, PBGC noted in Technical Update 26-1 that attrition-event reports seldom uncover situations requiring further agency scrutiny and generally provide limited value in identifying plans or sponsors that pose greater risk to the pension insurance system. PBGC also recognized that these events often arise in frozen plans with small active populations, making the reporting obligation burdensome relative to its usefulness. On that basis, PBGC determined that temporarily suspending attrition-event reporting would ease administrative and compliance costs while still allowing the agency to receive meaningful notice of significant workforce reductions through the separate single-cause event reporting rules. The temporary waiver applies regardless of whether another waiver or extension under PBGC’s reportable-event rules might otherwise have applied to the attrition event.

How long will the temporary waiver last?

Technical Update 26-1 temporarily suspends the obligation to report attrition events under PBGC reportable event regulations until the agency issues further guidance or adopts final regulatory changes addressing that requirement. The waiver will stay in place until a final regulation modifying the regulation as it relates to attrition events becomes effective.

Is reportable event reporting for other events changing?

No other reporting obligation has been changed. Technical Update 26-1 does not waive reporting of single-cause events, any other reportable event under ERISA 4043, any event reportable under another ERISA or PBGC provision, or any information specifically requested by PBGC.

Although PBGC has provided temporary relief from reporting attrition events, plan sponsors should continue to review participant reductions and other organizational changes carefully to assess whether any other PBGC notice obligation may still apply. Because the waiver is limited, employers should maintain processes to identify potential filing triggers and consult with advisors to ensure they remain compliant with all reportable event requirements.

Please contact your Milliman consultant to determine how this may impact your plan(s).

¹ Code of Federal Regulation Title 29 § 4043.23(a)(2). (September 30, 2026). National Archives. Retrieved September 22, 2026 from https://www.ecfr.gov/current/title-29/subtitle-B/chapter-XL/subchapter-E/part-4043/subpart-B/section-4043.23.