Partial Plan Termination: When Layoffs Make You 100% Vested

If your employer ended the employment of 20% or more of the people in its 401(k) plan during a plan year, the IRS presumes a partial plan termination. Everyone who left that year then becomes 100% vested in employer contributions, including the matching money the plan may have told you was forfeited.

Plans do not send a notice saying a partial termination happened. The determination sits in the plan’s records, and in practice the money comes back when someone asks for it. That request is short, and you can send it yourself.

The short version

• The test is a percentage. Count the people who left because the employer ended their employment, divide by everyone in the plan at the start of the year plus everyone who joined during it. At 20% or more, a partial plan termination is presumed.
• If it happened, the group is wider than the layoff. Every participant who left during that plan year and still has an account balance is fully vested, not just the people who pushed the rate over 20%.
• Only employer money is in dispute. Your own salary deferrals were always 100% yours. The question is the match, profit sharing and any other employer contribution.
• Ask in writing. A written claim for benefits starts a 90-day clock for an answer, so the letter should ask for the vesting determination, not just the balance.
• Routine turnover can rebut the presumption. A plant closing or a division shutdown is a stronger case than steady churn in a call center, so put the dates and the size of the cut in the letter.

What a partial plan termination is

Section 411(d)(3) of the tax code says a plan stays qualified only if it provides that, on a partial termination, the rights of all affected employees to benefits accrued to that date are nonforfeitable. The plan document has to say this. Most do, in a sentence almost nobody reads.

Whether a partial termination actually happened is a facts and circumstances question under Treasury Regulation 1.411(d)-2. The regulation names two routes: severance of a group of employees who were previously covered, and a plan amendment that excludes a group or cuts back on vesting.

Revenue Ruling 2007-43 turned that into arithmetic. If the turnover rate is at least 20%, the IRS presumes a partial plan termination. The rate is employer-initiated severances during the period, divided by the number of participating employees at the start of the period plus the number who became participants during it. In the ruling itself, 23% of participants left when one of four locations closed, and the partial termination was found.

Three details decide most cases. Vested and nonvested participants both count in the arithmetic. An employer-initiated severance includes a layoff caused by bad markets or a lost contract, so the reason behind the cut does not excuse it. Death, disability and retirement at or after normal retirement age are excluded.

The applicable period is normally one plan year. It stretches longer when there is a series of related severances, which is how a slow bleed over eighteen months gets counted as one event.

The 20% figure is a presumption, not a switch

An employer can argue the turnover was routine. The IRS looks at turnover in other years, whether the terminated employees were replaced, whether the replacements did the same work, held the same title and earned comparable pay. A business that loses a fifth of its staff every year and hires replacements has a defense. A business that closed a plant does not.

Voluntary quits are treated differently at the two stages. They generally do not count toward the turnover rate, because the rate is built on employer-initiated severance. Once a partial termination is established, though, the IRS says participants who left voluntarily during that period must be fully vested too.

Below 20% is not safe either. A partial termination can be found on a smaller cut when a plan amendment excludes a group of employees who were covered before, or when an amendment trims vesting rights. The percentage is the most common route, not the only one.

Who becomes vested, and in what

When a partial termination occurs through turnover, the IRS requires all participating employees who had a severance during the applicable period to be fully vested in their account balances. The rule is written in terms of the whole group, which is why the person at 20% vesting benefits as much as the person at 80%.

The IRS FAQ adds a practical definition. An affected employee is generally anyone who left employment for any reason during that plan year and still has an account balance in the plan. Some plans wait for five consecutive one-year breaks in service before forfeiting, and for those plans anyone without five breaks is still affected.

What gets vested is employer money. Salary deferrals are always 100% vested, and safe harbor 401(k) and SIMPLE plan contributions vest immediately. Traditional matching contributions follow one of two schedules: a three-year cliff, or two to six years of graded vesting at 20%, 40%, 60%, 80% and 100%. Automatic enrollment plans that require an employer contribution vest it after two years.

One trap sits in the plan document. A plan may treat anyone who is 0% vested as cashed out and forfeit the balance immediately. The IRS issue snapshot on partial terminations flags those deemed cash-outs as the provision to check, because a forfeiture that happened before the partial termination still has to be undone.

A worked example

An employer starts the plan year with 412 participants and hires 58 during the year, so the denominator is 470. Layoffs account for 104 departures. That is 22.1%, above the line, so a partial plan termination is presumed for that plan year.

Jordan was one of the 104. He had two years of service under a two to six year graded schedule, so the plan showed him 20% vested in $14,200 of match and profit sharing. His statement listed $2,840 as vested and $11,360 as subject to forfeiture.

After the partial termination, the whole $14,200 is his. If the plan already moved the $11,360 out, the employer has to make him whole, and the IRS points employers at its correction program for exactly this failure.

A smaller cut can reach the same result by a different road. A division of 200 participants loses 31 people when the work is moved to another state, which works out to 15.5%. No presumption applies, but the severance of a group that was previously covered is the fact the regulation names first, so the case is still worth making in writing.

What the plan owes if it got this wrong

The IRS FAQ is blunt about the remedy. Participants who improperly incurred forfeitures are owed more benefits. To the extent the forfeited money was spread to other participants and cannot be recovered, the employer is responsible for making the affected participants whole.

So the answer to a denial is not always the end. A plan that forfeited balances it should have vested has a qualification failure, and the employer can fix it through the IRS Voluntary Correction Program. You do not file that correction. You ask the plan to look at the year again, in writing, and keep the paper.

How to find out whether it happened

Start with the summary plan description, which has to describe when you vest. Ask the administrator for the vesting schedule and for your account statement as of the date you left. The statement shows the vested and unvested split, which is the number you are arguing about.

Then send three questions. Was a partial plan termination determined for the plan year in which I left. What was the participant count at the start of that year and how many participants had an employer-initiated severance during it. How was my nonvested balance treated, and was any part of it forfeited or reallocated.

A written request for plan documents has a 30-day deadline, and an administrator who ignores it can be personally liable to you for up to $110 a day in the court’s discretion. A claim for benefits gets 90 days, with one 90-day extension if the plan explains the delay in writing before the first period ends.

The public record helps before you write. A plan’s annual government filing reports how many participants it had at the start of the year, how many joined and how many left, so a sharp drop shows up in the filings even when nobody tells you about it. A search of a former employer in FindMyPlan lays out the plan’s filing years in one place, which is enough to date the year you need to ask about.

One caution about the free government tools. The Labor Department’s Retirement Savings Lost and Found and the Social Security notice are built largely on Form 8955-SSA reports, which list separated participants with vested benefits. A balance the plan wrongly treated as forfeited may never have been reported, so an empty search there does not settle the question.

If the plan says no

A denial has to be in writing and has to explain the reason, under the claims procedure in 29 CFR 2560.503-1. Read it against the plan document and the ruling. If the letter never addresses the vesting year, that gap is the appeal.

You can also bring the question to the Labor Department’s Employee Benefits Security Administration, which takes inquiries at askebsa.dol.gov and 1-866-444-3272. A suit to recover benefits under section 502(a)(1)(B) of ERISA is the last step, and it is the one place where the vested amount can be ordered paid.

Watch the clock. A fiduciary breach claim has to be filed within six years of the breach, or three years after you had actual knowledge of it, whichever comes first. That is long enough for a plan correction, and short enough that a letter sent this month is worth more than one sent next year.

Find your situation

• The company was sold or merged, which decides whether the buyer or the seller owes you.
• The employer failed, and a custodian may have wound the plan up.
• The balance was small and disappeared, which is how most force-outs start.
• You want back into the online account to read the statement before you argue about vesting.
• You have an employer name and no paperwork, so start with the ten-step guide.
• It was a pension, not a 401(k), and the PBGC matters more than the recordkeeper.

What FindMyPlan shows for a former employer

You search with a company name and nothing else. FindMyPlan covers about 2.3 million plans and 21 million public filings for plan years 1999 through 2025, plus about 465,000 plan transfers and company changes traced through SEC records.

A free account shows which plans matched and how many filings exist. Retirement Essentials adds the plan history year by year, where the money went when a plan merged or closed, who to contact, and a records request you can send as written.

For this question the filing years do the work. They let you name the plan year in your letter instead of asking the administrator to guess which year you mean, and a plan sponsor answers a dated question faster than an open one.

What is a partial plan termination?

A partial plan termination is a year in which a large share of a retirement plan’s participants lose coverage, usually through layoffs, so the plan must fully vest the affected employees. The IRS presumes it when 20% or more of participants had an employer-initiated severance during the applicable period, under Revenue Ruling 2007-43. It can also be found below that rate when a plan amendment excludes a covered group or cuts back on vesting.

Does a partial termination make me 100% vested?

Yes, if you left during the plan year of the partial termination and still have an account balance. The IRS requires all participating employees who had a severance during that period to be fully vested in the amounts credited to their accounts, and that includes people whose own departure was voluntary. Your salary deferrals were already 100% vested, so the change is in the match and other employer contributions.

How is the 20% turnover rate calculated?

Divide the number of participating employees who had an employer-initiated severance during the period by the number of participants at the start of the period plus those who became participants during it. Vested and nonvested participants both count. In Revenue Ruling 2007-43, 23% of participants left when one of four locations closed, and the IRS found a partial termination.

How long do I have to claim a forfeited match?

A claim for benefits starts a 90-day clock for the plan to answer, with one 90-day extension if the plan explains the delay in writing. A suit over a fiduciary breach under ERISA has to be filed within six years of the breach, or three years after you had actual knowledge, whichever comes first. Send the letter as soon as you have the plan year and the vesting numbers.

What if the employer says the turnover was routine?

That is the standard defense, and it turns on facts. The IRS looks at turnover in other years, whether terminated employees were replaced, whether the replacements did the same work and earned comparable pay. A closed plant or a sold division is not routine. A business with steady annual churn may be able to rebut the presumption.

Does the plan have to tell me a partial termination happened?

Plans do not send a separate notice for it. You learn it from the plan document, your account statement, or the participant counts in the plan’s annual government filings. A written request to the plan administrator is how you get an answer that names the plan year.

Sources

• IRS Revenue Ruling 2007-43 (the 20% turnover presumption, the rate formula, and full vesting for everyone who left during the period)
• IRS FAQ: partial plan termination (affected employees, routine turnover factors, voluntary quits, restoring forfeitures)
• IRS issue snapshot: partial termination of plan (turnover rate example, deemed cash-outs, amendments)
• IRS: retirement topics, termination of plan (100% vesting on termination, participant rights)
• 26 U.S. Code section 411 (minimum vesting standards, three-year cliff and two to six year graded schedules)
• Treasury Regulation 1.411(d)-2 (facts and circumstances test for partial termination)
• DOL: What You Should Know About Your Retirement Plan (401(k) vesting schedules, rights on plan termination)
• 29 CFR 2560.503-1 (claims procedure, 90 days plus one 90-day extension)
• 29 U.S. Code section 1132 (suit to recover benefits, and the penalty for failing to furnish documents)
• 29 CFR 2575.502c-1 (the section 502(c)(1) penalty adjusted to $110 a day)
• 29 U.S. Code section 1113 (limitation on actions, six years or three years after knowledge)

Retirement planning takeaways from this article

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