A missed deferral election happens when an employee asks to contribute to the 401(k) plan and payroll never starts the deduction, or when an eligible employee is never offered the chance to enroll at all. Either way, the employee lost the opportunity to save on the terms the plan promised. For the plan sponsor, that is not a payroll hiccup to quietly fix going forward. It is an operational failure that the sponsor must find, correct, fund and document.
This guide walks through why these errors are a fiduciary matter, how they usually happen, what the correction generally involves, and what a sponsor can and cannot hand off to a provider.
Why a Missed Enrollment Is a Fiduciary Problem, Not a Clerical One
The plan document is a promise. It says who becomes eligible, when they enter, how elections are made and what the employer contributes. When the plan is operated differently from the document, the IRS treats it as an operational failure, and the plan’s tax qualification depends on correcting it. We cover that broader risk in what happens when your plan records disagree.
The key point sponsors miss: you cannot simply start the deferral today and move on. The employee lost a savings opportunity, and in most plans they also lost the employer match that would have followed. The correction is about restoring the employee to roughly where they would have been, not just stopping the error.
How Missed Deferrals and Missed Enrollments Usually Happen
- The election form never reached payroll. An employee enrolled on the recordkeeper portal, but the change never flowed into the payroll system.
- Eligibility was tracked by hand. Nobody noticed the employee hit the plan’s service requirement, so no enrollment packet went out. Our guide to 401(k) eligibility and entry dates covers where this goes wrong.
- Automatic enrollment wasn’t applied. The plan has an automatic enrollment feature, but new hires were set up at zero percent in payroll.
- A rehire was treated as a new hire. The employee should have re-entered immediately but was made to wait again. See rehires and breaks in service.
- Excluded compensation. Deferrals were taken from base pay only when the plan’s compensation definition includes bonuses or overtime.
- A payroll or recordkeeper conversion dropped elections. Deferral percentages did not carry over to the new system.
What the Correction Generally Involves
The IRS Employee Plans Compliance Resolution System (EPCRS) sets out correction methods for these failures. The exact method and the size of the corrective contribution depend on the type of error, how long it lasted, when it was found and what your plan document says. Treat the steps below as the framework, and confirm the specific calculation with your document provider or plan administrator.
1. Identify every affected employee
Start with a full list. That means every employee who was eligible and not enrolled, every election that was not implemented, and every election implemented at the wrong rate. One discovered error often points to a systemic cause that affected others. A structured payroll-to-recordkeeper reconciliation is usually how the full population is found.
2. Determine the correction period
For each employee, establish when the deferral should have started and when the error was fixed. That window drives everything else. It comes from employer-only data: hire dates, hours, election dates and payroll records.
3. Calculate the missed deferral opportunity
The employee cannot go back and defer from pay they already received. Instead, EPCRS generally requires the employer to make a corrective contribution that replaces a portion of the lost deferral opportunity. The required portion varies by situation, and EPCRS includes reduced-cost methods for errors caught early and for certain automatic enrollment errors, which often come with specific notice requirements. The corrective amount is employer money, deposited to the plan, and is not taken from the employee’s pay.
4. Restore the missed match in full
If the plan provides a matching contribution, the match the employee would have received on the missed deferrals generally must be contributed. This is where sponsors often underestimate the cost.
5. Add earnings
Corrective contributions are generally adjusted for lost earnings from the date the money should have been in the plan. The method should be applied consistently and documented.
6. Start the deferral correctly going forward
Fix the payroll setup and confirm the first corrected paycheck actually shows the right deduction. A correction that never reaches the payroll file isn’t a correction.
7. Notify affected employees when required
Some correction methods require a written notice to each affected employee explaining the error and their right to adjust their election. Keep a copy of the notice and proof of delivery. Our guide to automatic enrollment notices covers the related notice obligations.
8. Choose the correction channel
Many operational failures can be self-corrected under EPCRS if the plan has established practices and procedures and the correction is timely. Others, depending on severity and timing, call for a filing with the IRS. That judgment is fact-specific. Get advice before deciding.
A Quick Self-Check for Sponsors
- Does payroll receive every election change from the recordkeeper, and does someone confirm it was applied?
- Who tracks when each employee becomes eligible, and how?
- If the plan uses automatic enrollment, does payroll’s default rate match the adoption agreement?
- Are deferrals taken from every pay type the plan document includes?
- Are rehires checked against prior service before their entry date is set?
- Was a deferral-rate audit done after your last payroll or recordkeeper change?
- Is there a written procedure for correcting a missed election when one is found?
- Is every past correction documented, including calculations, deposits and notices?
Where Sponsors Get Hurt
- Fixing it going forward only. Starting the deferral without the corrective contribution leaves the failure uncorrected.
- Letting the employee “catch up” instead. Having the employee defer extra from future pay is not the employer correction the rules generally require.
- Correcting one person when the cause was systemic. If the payroll mapping was wrong, others were affected too.
- Waiting. The reduced-cost correction options generally depend on how quickly the error is found and fixed.
- No paper trail. An auditor or the IRS will want to see the calculation, the deposit and the notice. Our audit readiness checklist covers what to keep.
What You Can Delegate and What You Can’t
A capable administrator can monitor eligibility, reconcile elections against payroll, calculate the corrective contribution and prepare the notice. What a provider cannot supply is the employer’s own data: accurate hire and rehire dates, hours, pay codes and the payroll file itself. And the decision to fund a correction is the employer’s to make, with employer money. A missed deferral is related to, but different from, a deposit that was withheld and sent late. For that error, see our guide to correcting late deferral deposits.
If you use an administrator, ask directly: who reconciles elections to payroll each pay period, and who tells us when an employee becomes eligible? If the answer is “you do,” the risk is still on your desk.
How Admin316 Helps
Admin316 serves as a 3(16) plan administrator, which means we take on the day-to-day operational duties where missed elections start: eligibility tracking, enrollment, payroll data review and correction support. If your plan has already found a problem, we can help map the affected population and the correction path. See what else can go wrong in what happens if your 401(k) is out of compliance.
Most importantly, Admin316 accepts appointment as the plan’s ERISA 402(a) named fiduciary, the role with overall authority to control and manage the operation of the plan. Most providers decline that appointment. We accept it, so the question of who is watching enrollment and elections has a clear answer.
Not sure every eligible employee is enrolled at the right rate? Book a plan review with Admin316 and we’ll check your elections against payroll.
