Left-Behind 401(k)s Are a Recordkeeper Problem Too: What They Cost and How to Stop Creating Them
For savers, forgotten 401(k)s are lost money. For the recordkeepers, custodians and IRA providers holding 31.9 million of them, they are missing participants, uncashed checks and force-out IRAs that shrink. Why auto-portability covers only part of it, and a playbook for stopping accounts being left behind at the job change.
TrustRails Team
• Regulatory & Platform EngineeringLeft-behind 401(k)s cost the institutions that hold them, not just the savers who forgot them. Every account nobody moved after a job change becomes recurring administration, a missing-participant exposure, an uncashed check or a safe harbor IRA that loses value. Auto-portability addresses only balances of $7,000 or less inside one network. The durable fix is upstream: make the plan-to-plan rollover easy enough that the account moves while the participant is still reachable.
- left-behind 401(k) accounts (July 2025)
- 31.9M
- assets in those accounts
- $2.1T
- of displaced accounts moved in their first year
- 12.8%
- plans adopting auto-portability as of Sept 30, 2025
- 20,997
Sources: Capitalize (2025), via 401(k) Specialist; PensionBee (2025); 401(k) Specialist (Dec 2025). Capitalize and PensionBee sell rollover-related services.
When Yahoo Finance covered forgotten retirement accounts in October, we answered it for savers in a companion article. This one is for the other side of the account: the recordkeepers, custodians, IRA providers and plan sponsors who carry those 31.9 million accounts on their books.
What does a left-behind 401(k) cost the plan and its recordkeeper?
Capitalize's estimate of 31.9 million accounts and $2.1 trillion, up almost 30% since mid-2023, is contested by industry groups as a proxy for “every potential rollover” rather than genuinely lost money. Take it as an order of magnitude. Even at half the size, each of those accounts carries four kinds of cost for the institution holding it:
- Recurring administration with no offsetting revenue growth. Every left-behind account still receives statements, fee disclosures, summary annual reports and required notices, and still appears in the plan’s participant count. Asset-based revenue on a static small balance rarely covers it.
- Missing participants, which the DOL treats as a fiduciary issue. EBSA's best-practices guidance names returned mail, stale contact data and uncashed checks as red flags, and expects plans to address “the transfer of appropriate plan information” when recordkeepers change. Accounts nobody has touched since a job change are where those red flags accumulate.
- Uncashed distribution checks. A force-out check that is never cashed does not close the account; it converts a participant into a missing participant with a liability still on the plan’s books. The DOL’s guidance specifically flags a substantial number of stale uncashed distribution checks.
- Safe harbor IRAs that shrink, and the questions that follow. Principal-preservation products plus account fees can leave a forced-out balance lower than when it arrived. PensionBee puts $28.4 billion in safe harbor IRAs today, heading past $43 billion across roughly 13 million accounts by 2030, with only 12.8% of displaced accounts moved in their first year. PensionBee sells a competing safe harbor IRA, so treat the projection accordingly; the direction is not in dispute.
What do the $1,000 and $7,000 thresholds require of a plan fiduciary?
SECURE 2.0 Section 304 raised the mandatory-distribution cap from $5,000 to $7,000 for distributions after December 31, 2023. The plan's options, and the obligations that come with each, depend on the vested balance:
| Vested balance | What the plan may do | What the fiduciary takes on |
|---|---|---|
| $1,000 or less | Cash out by check, or roll to an IRA | If the check is never cashed, the participant is now a missing participant. FAB 2025-01 allows a transfer to state unclaimed property under conditions. |
| $1,000 to $7,000 | Roll to an automatic rollover (safe harbor) IRA without consent | Prudent only inside the 404a-2 safe harbor: principal-preserving product, fees no higher than comparable IRAs, written agreement, SPD/SMM disclosure. |
| More than $7,000 | Nothing without the participant’s election | The account stays. Statements, fee disclosures, notices and the participant count continue indefinitely, as does the duty to keep finding the owner. |
The middle row is the 29 CFR 2550.404a-2 safe harbor. It protects the fiduciary's choice of IRA provider, and it does so by requiring a product “designed to preserve principal and provide a reasonable rate of return” consistent with liquidity. That requirement is why the accounts sit in cash-like holdings, and why a balance can arrive at $3,000 and be worth less years later once fees are netted. The safe harbor is working as designed. The design assumes the participant will come back for the money, and only 12.8% do in the first year.
Does auto-portability solve the problem?
Partly, and the part it solves it solves well. Under SECURE 2.0 Section 120, a safe harbor IRA balance can follow the participant into a new employer's plan without a signed request. The Portability Services Network, owned by Alight, Empower, Fidelity, Principal, TIAA and Vanguard and operated by Retirement Clearinghouse, says its owners represent about 82 million workers across more than 185,000 plans. 401(k) Specialist reported 20,997 adopting plans as of September 30, 2025, including 9,200 of Fidelity's 26,500 corporate plans and more than 11,000 at Empower.
Three limits remain. It covers only balances of $7,000 or less that were already forced out, so the large accounts that make up most of the $2.1 trillion are outside it. It works only when the sponsor has elected it and both recordkeepers are in the network. And it is a network, not a protocol: it does not make the ordinary plan-to-plan rollover electronic for anyone else. A recordkeeper that has adopted auto-portability still processes every other rollover the way it did before.
Why is the rollover itself the root cause?
Accounts are left behind at one moment: the job change. At that moment, moving the money means working out who holds the old plan, obtaining forms from two institutions, sometimes a notary or Medallion Signature Guarantee, and then a check. The GAO called mailing rollover checks to participants “archaic” in 2013; in 2024 it found nearly one-third of participants still receive one. In Capitalize's 2024 survey, 42% of savers said their rollover took two months or longer. Every slow step is a place to stop, and stopping is free until the force-out or the cash-out arrives.
Consumer guidance still treats a check payable to the custodian as the finish line. A 24/7 Wall St. piece syndicated by Yahoo Finance in September walks a saver with five old 401(k)s through making sure every check is made out to the new custodian, not to him. That is the right tax outcome, with no 20% withholding and no 60-day clock. It is also still a printed check, usually mailed to the participant to forward, with the money out of the market in between (our direct vs. indirect rollover guide covers the participant-side rules). Brokerage assets move between firms over ACATS in days, under deadlines FINRA sets for each side. Plan-to-plan rollovers have no common form, identifier, channel or clock.
What does IRS Notice 2026-49 change for recordkeepers?
Nothing yet, and potentially a great deal. The Notice proposes optional sample forms, a five-step plan-to-plan procedure in which the participant asks once and the two institutions handle the rest, and a rollover identification number so plans can coordinate without re-sending SSNs. Section IV lists what Treasury is considering next: ending the rule that lets rollover checks be mailed to participants, requiring electronic transfer where both plans can support it, and safe harbors for plans that use the standard procedure. Comments closed October 23, 2026.
For a recordkeeper, the practical reading is that the direction is fixed and the timing is open. Our explainer covers what the Notice says; the Rollover Rails white paper covers the six changes that would turn it into working infrastructure, including a streamlined variant for auto-portability batches. No plan or platform can claim Notice 2026-49 compliance or a safe harbor today, because none exists.
Settle rollovers custodian-to-custodian at the job change
TrustRails connects the sending and receiving custodian directly: the participant asks once, both sides confirm, funds move trustee-to-trustee, and every step is recorded.
Where does TrustRails fit?
TrustRails is settlement infrastructure for the general case: a direct, trustee-to-trustee rollover between any two custodians, for any balance, whether or not either is in a portability network. The participant starts the request once, inside the recordkeeper's own offboarding or enrollment flow via our API or embeddable widget. Both custodians review and affirmatively agree before anything moves. Funds go directly from sending to receiving custodian; TrustRails never takes custody. Personal data is encrypted, and every state change is an append-only, timestamped event the participant, both custodians and an auditor can see.
It complements auto-portability rather than replacing it: PSN handles the $7,000-or-less safe harbor IRA case inside its network, and TrustRails handles everything else. We do not locate missing participants, offer IRAs, give investment advice or act as a fiduciary. The claim is narrower and, we think, more useful: a rollover that completes in the weeks after a job change is an account that never has to be found.
The playbook: what to do now
Recordkeepers
- •Instrument the termination event. Measure how many days pass between a participant’s separation and either a completed rollover or a force-out, and where the time goes.
- •Offer the roll-out at offboarding, electronically, with the receiving institution confirming before anything is cut. A mailed check is a chance for the money to stall.
- •Accept roll-ins the same way. A new hire who can move an old balance in during enrollment never becomes someone else’s missing participant.
- •Map intake fields to the IRS Notice 2026-49 data set now, including where you require more than the forms ask for, such as a full SSN.
IRA and safe harbor IRA providers
- •Document the 404a-2 conditions per plan: the product, the fee comparison and the written agreement. That file is what an auditor asks for.
- •Make the exit easy. An account holder who wants to consolidate should be able to initiate a trustee-to-trustee transfer without a notary, a Medallion guarantee or a check mailed to them.
- •Join or interoperate with auto-portability for balances of $7,000 or less, and have an electronic plan-to-plan path for everything above it.
Plan sponsors and advisors
- •Ask your recordkeeper for the DOL red-flag numbers: missing participants, returned mail, stale uncashed checks. If it cannot produce them, that is a finding.
- •Decide the auto-portability election deliberately, and check SECURE 2.0 plan amendments before the December 31, 2026 deadline.
- •Ask how long an incoming and an outgoing rollover actually take at your recordkeeper, step by step.
What the numbers do and do not say
Capitalize and PensionBee both sell services that benefit from a large forgotten-account problem, and NAPA and ASPPA have argued the 31.9 million figure counts every un-rolled account as “forgotten.” PensionBee's projection does not model auto-portability's growth. We have left out figures we could not trace to a primary source, including a widely repeated claim about how many safe harbor IRAs lose value over eight years. None of the caveats changes the operational picture a recordkeeper sees in its own returned-mail and uncashed-check queues.
Frequently asked questions
What are the Department of Labor’s red flags for a missing-participant problem?
EBSA’s January 2021 best-practices guidance lists five: more than a small number of missing or nonresponsive participants; more than a small number of terminated vested participants past normal retirement age who have not started benefits; missing, inaccurate or incomplete census and contact data; no sound procedures for returned mail and undeliverable email; and no sound procedures for uncashed checks, such as no journal of them or a substantial number of stale ones.
What does the automatic rollover safe harbor in 29 CFR 2550.404a-2 require?
To be deemed prudent when forcing a small balance into an IRA, the fiduciary must have a written agreement with the IRA provider, invest the money in a product designed to preserve principal and provide a reasonable rate of return consistent with liquidity, ensure fees do not exceed what the provider charges comparable IRAs, describe the arrangement in the SPD or an SMM, and avoid a prohibited transaction.
Did SECURE 2.0 change the 401(k) force-out threshold?
Yes. Section 304 raised the mandatory-distribution cap from $5,000 to $7,000 for distributions made after December 31, 2023. Balances of $1,000 or less may still be cashed out; balances between $1,000 and $7,000 that the participant does not direct must be rolled to an IRA rather than paid in cash.
Who is in the Portability Services Network, and what does auto-portability not cover?
PSN is owned by Alight, Empower, Fidelity, Principal, TIAA and Vanguard, with Retirement Clearinghouse as operator; the owners say they represent about 82 million workers across more than 185,000 plans. Auto-portability moves only balances of $7,000 or less that were forced into a safe harbor IRA, only when the plan sponsor has adopted it and the new employer’s recordkeeper is in the network. Balances above $7,000, and any rollover outside the network, still go through the ordinary paper process.
What is Field Assistance Bulletin 2025-01?
A temporary enforcement policy EBSA issued in January 2025. The Department will not pursue ERISA section 404(a) claims against fiduciaries who voluntarily transfer benefits of $1,000 or less owed to missing participants, including uncashed checks, to a state unclaimed-property fund, provided the conditions in the bulletin are met. It binds only the Department, not participants.
Does IRS Notice 2026-49 change how recordkeepers process rollovers?
Not yet. The Notice proposes optional sample forms, a five-step plan-to-plan procedure and a rollover identification number, and asks whether to require electronic transfer and end checks mailed to participants. Nothing is mandatory and no safe harbor exists. The comment period closed October 23, 2026; final guidance will say what, if anything, becomes required.
Is a rollover check payable to the new custodian still a paper-check rollover?
Yes. Making the check payable to the receiving custodian for the participant’s benefit avoids 20% withholding and the 60-day deadline, but the check is still printed and, in the GAO’s 2024 finding, nearly one-third of participants still receive it themselves and must forward it. The money is out of the market and the participant is the courier.
TrustRails builds infrastructure for direct, trustee-to-trustee retirement plan rollovers between custodians. If you run rollovers, force-outs or roll-ins at a recordkeeper, custodian or IRA provider and want fewer accounts left behind, talk to us.
For general information only; not tax, legal, or investment advice. ERISA fiduciary obligations, mandatory-distribution rules and the automatic rollover safe harbor have conditions and exceptions; consult ERISA counsel about your plan. Third-party estimates are attributed to their publishers, some of which sell rollover-related services. IRS Notice 2026-49 is proposed guidance.