Form 5500-SF or Form 5500: small plan, large plan, and the pair of caps the count picks

The line is 100 participants at the start of the plan year

Every rule on this site that says "small plan" or "large plan" comes back to one count: participants on the first day of the plan year. Under 100 the plan is small and usually files the short Form 5500-SF. At 100 or more it is large and files the full Form 5500 with its schedules and an accountant's report. Department of Labor, Form 5500

The test is short. Under the 2025 Instructions for Form 5500, Who Must File and What To File, page 8, a small plan is a plan with fewer than 100 participants as of the beginning of the plan year. The count is taken once, at the start, so a plan that grows past 100 in March is still small for that year's return.

The 80-to-120 rule

The line has a buffer so plans do not bounce between forms every year. A plan that filed as small at 95 participants and now has 115 may file as small again.

Under 29 CFR 2520.103-1(d), a plan with between 80 and 120 participants at the start of the plan year that filed a return for the prior year may elect to file in the same category, small or large, as that prior return.

It is an election, not a requirement, and the clock does not make it for you. It flags a count that sits in the band and leaves the election to whoever knows what the prior return used. The flag changes nothing in the fee maths, so the cap the clock prices is always the one the count on the line picks. 29 CFR Part 2520

Which line you count on, and the first-year trap

For years a 401(k) counted every employee eligible to defer, whether they had put a dollar in or not. That pushed plans over 100 on eligibility alone. Defined contribution plans now count only people who hold an account balance. Welfare and defined benefit plans did not change.

From plan years beginning in 2023, a defined contribution pension plan counts the participants with account balances at line 6g(1), except that a plan checking the first return box uses the end of year figure at line 6g(2); welfare and defined benefit plans still count total participants at line 5, under 88 FR 11984.

The exception is the one to write down. A plan filing its first return counts line 6g(2), account balances as of the end of the plan year. A new 401(k) that opened the year at nothing and closed it with 140 funded accounts is large for that first year, and a first return is exactly the kind that gets filed late.

For a late plan book this is where the money is. A plan that was large under the old count can be small under the new one, so the category moves between years for the same plan. The clock reads the count and the plan type per plan year. It has no input for a first return, so it cannot tell you a plan year was one, and the end of year figure is a count you work out and enter yourself.

Why the count decides which pair of caps applies

The Department of Labor's late penalty does not care about size. Under ERISA section 502(c)(2) the Department may assess up to $2,739 a day for 2026, unchanged from 2025 and carried into 2026 by the Department's notification at 91 FR 31358, published 27 May 2026, and the same for a plan with 12 participants as for one with 1,200. What changes with size is the price of fixing it, and it does not change by one number. It changes by a pair.

Under 78 FR 6135, Section 3.03(b), the DFVCP fee is $10 a day capped at the greater of $750 per annual report or, where one submission covers more than one delinquent report for the plan, $1,500 per plan for a small plan, and at the greater of $2,000 per annual report or, for a submission covering more than one delinquent report for the plan, $4,000 per plan for a large plan.

Read the "greater of" twice, because it is the part people get backwards. It is not the lower of the two. One late year for a small plan caps at $750. Four late years for that plan in one submission cap at $1,500, not $750 four times over. The large pair behaves the same way, $2,000 against $4,000. EBSA, DFVCP

Under 78 FR 6135, Section 3.03(b), if the plan was a large plan in any year the submission covers, the large plan caps apply to the whole submission.

That rule catches a mixed run: three small years and one large year for the same plan are priced at the large pair throughout. Two flat amounts sit outside the pairs, one for 501(c)(3) small plans and one for top hat and apprenticeship plans, and the DFVCP page carries the whole schedule.

Under 29 CFR 2520.103-1(b)(5), the annual report of a plan with 100 or more participants normally includes a report from an independent qualified public accountant.

That is the other reason the line matters. "Late and large" means engaging an auditor before the DFVCP submission goes in. Whether a small plan can file without one turns on conditions this clock does not evaluate, so it does not say.

Form 5500-SF against Form 5500

The Department of Labor daily figure in the last row is the 2026 figure, unchanged from 2025, and the notification carrying it into 2026 is at 91 FR 31358, published 27 May 2026. Sources: Department of Labor, Form 5500 EBSA, DFVCP

Worked example: a count one under the line

This example came out of the engine, not off a calculator. The count is one under 100, so the plan reads small and the small pair of caps prices the late year. The same count is inside the 80 to 120 band, and the clock says so on its own row, because the election is the reader's to make and not the engine's.

Where this lands for a plan book

Hold one plan and you can run it, read the category and stop. Hold two hundred and the count is the column most likely to be wrong, because it came off a census file that predates the counting change. Paste the list, then check two sets by hand: the 80-to-120 band, and any plan filing a first return. The TPA and broker page covers the list format.