# Employee benefit plan audit and Form 5500 support

Canonical: https://finbryn.com/us/services/for-accounting-firms/employee-benefit-plan-audit-form-5500-support

Finbryn provides Form 5500 and employee benefit plan audit preparation support for third-party administrators and accounting firms: draft data packs, audit request lists, participant data tie-outs and contribution timeliness workpapers. The plan administrator signs and files on EFAST2, and the plan's independent auditor issues the report.

Most 401(k) plans need two things each year that eat the same few weeks of a TPA's or accounting firm's capacity: a Form 5500 filed on EFAST2, and for plans with 100 or more participants with account balances at the start of the plan year, an independent audit attached to it. The filing is due by the last day of the seventh month after the plan year ends, July 31 for a calendar-year plan, and a timely Form 5558 extends it by two and a half months, to October 15.

Most of the hours in this work are not judgment. They are chasing a census file, tying payroll registers to recordkeeper deposits, building the list of what the auditor needs, and testing whether each employee deferral reached the trust on time. That is the layer we take. A firm sends the plan's data and the recordkeeper and payroll reports; we return a tied-out participant file, a contribution testing workpaper, an audit request list already marked up against what has been received, and a draft data pack for the Form 5500 and its schedules.

The edges are firm. The plan administrator reviews, signs and files the 5500 using EFAST2 credentials, and the independent auditor issues the opinion on the plan's financial statements. Defined benefit actuarial schedules, including Schedule SB, are excluded because the plan's enrolled actuary prepares and signs them. Our work is the preparation support underneath, in your firm's templates, so your reviewers open a workpaper and not a mystery. Capacity is the point: the same four workpapers, repeated across every plan on your list, in the weeks when your own staff are busiest.

For the sponsor's own books behind a plan audit, see [audit support services](/services/audit-compliance-support).

Plans with a defined benefit side also need [actuarial services](/services/actuarial-services).

What you get: Form 5500 draft data pack for the plan administrator's review and EFAST2 filing; Audit request (PBC) list tailored to the plan's recordkeeper and payroll sources; Participant data tie-out of census, payroll and recordkeeper balances; Contribution timeliness testing workpapers by pay date; Reconciliation of the trust statement to the plan's financial statements; A tracker of open requests so the auditor's fieldwork stays on schedule

Software we work in: EFAST2, Excel, Google Sheets, Karbon, Canopy, ADP, Paychex, Gusto

## What is included

A standard engagement for one defined contribution plan covers four workpapers. The first is a participant data tie-out: the census from the plan sponsor, payroll registers by pay date and the recordkeeper's contribution and balance reports are matched, and every difference is listed with a probable cause. The second is contribution timeliness testing, with each pay date, the date deferrals were withheld, the date they were deposited and the number of business days between them. The third is the audit request list, built from the plan's structure and the auditor's standard template, with received and outstanding items tracked. The fourth is a draft data pack for the Form 5500, with the numbers the filing needs from the plan's financial statements, ready for the administrator's review.

Where the plan has a trust statement, we also reconcile it to the draft financial statements so the audit starts from numbers that agree. Everything is delivered in Excel or in your practice-management workflow, with the formulas left visible.

## How the process works

We start by confirming scope with the firm: plan type, plan year end, recordkeeper, payroll system and which of the four workpapers are wanted. The firm or plan sponsor then sends source files through its own secure channel. We load the census and payroll data, run the tie-out and send back a list of exceptions within the date agreed at kickoff, so the sponsor can fix data problems before the auditor arrives.

Contribution timeliness comes next. DOL regulation 29 CFR 2510.3-102 treats participant contributions as plan assets as soon as they can reasonably be segregated from the employer's general assets, and no later than the 15th business day of the month after they were withheld. Plans with fewer than 100 participants have a safe harbor of seven business days. We test each pay date against both and flag late deposits with the number of days late, so the firm can decide how the late deposit is corrected and reported. We never decide that for the plan.

## Who this is for

The buyer is a firm, not a plan sponsor. TPAs with a filing season that outgrows their staff use us for data prep and workpapers. Accounting firms with an employee benefit plan audit practice use us when fieldwork and request-list building fall in the same weeks as their other deadlines. Firms that audit a handful of plans a year and cannot justify a full-time hire use us for the testing and tie-out layer only.

It is not a fit for a plan sponsor looking for someone to be named as the plan administrator, or for a firm that needs the audit report itself written. We prepare, you review and sign.

## Common problems we fix

Census files that do not match the payroll register are the most common problem, usually because of terminated employees, rehires or a mid-year payroll change. Second is the audit request list built from scratch every year, because last year's list lives in one person's inbox. Third is deposit dates taken from a recordkeeper summary that shows the date the money was invested, not the date it left the employer's account. That distorts the timeliness test. Fourth is a Form 5500 data pack that is assembled the week of the deadline with no tie-out behind it. Fifth is loan and distribution testing left to the auditor's sample when the firm could have caught the exceptions in advance.

## Software and integrations

We work in the files and portals your firm already uses. Census and payroll data arrives as exports from ADP, Paychex, Gusto or the sponsor's own system, and balances arrive from the recordkeeper's reporting portal. Workpapers are built in Excel, with a clean copy placed in Karbon, Canopy or your practice-management tool. The Form 5500 itself is entered and filed by the plan administrator, or by the firm acting for the administrator, on the Department of Labor's EFAST2 system. We do not hold EFAST2 credentials and do not file on anyone's behalf.

## Privacy and consent

Plan data includes Social Security numbers and account balances, so we ask for the minimum fields the test needs and for data to arrive over your firm's secure channel. Where tax return information is involved, the signing preparer obtains the client's written consent before it is shared with a service provider, consistent with IRC section 7216, and we treat Form 5500 engagements the same way. Files are returned to you, and retention follows your engagement letter. Details of the controls we apply are on our security page.

## What it costs

Pricing is per plan and depends on the number of participants, the number of payroll sources and which workpapers you want. We do not publish a per-filing price, because a plan with one payroll and a clean recordkeeper file takes far less time than one with three payrolls and a mid-year recordkeeper change. We quote after seeing a sample of the census and one payroll register, in writing, before work starts. Capacity for firms with many plans is scoped as a recurring engagement and covered on our [pricing page](/us/pricing).

## Timeline and onboarding

Setup takes about a week: we agree scope, match your workpaper templates and run a test on one prior-year plan so you see the output before the busy season. After that, each plan runs on a calendar tied to the plan year end. EBP fieldwork clusters in the late spring and the weeks before the October extended due date, so we ask firms to book capacity early. For similar capacity beyond benefit plans, see [review support](/services/for-accounting-firms/review-support) and [PBC lists](/services/audit-compliance-support/pbc-lists).

## The process

1. **Scope and templates**: We confirm plan type, year end, recordkeeper, payroll sources and the workpapers wanted, and adopt your firm's templates.

2. **Data intake**: Census, payroll registers and recordkeeper reports arrive over your secure channel with only the fields the tests need.

3. **Participant tie-out**: We match census, payroll and recordkeeper balances and list every exception with a probable cause.

4. **Timeliness testing**: Each pay date is tested against the deposit date and the DOL timing rule, with late items flagged for your decision.

5. **Request list and tracker**: The audit request list is built from the plan's structure and tracked as items arrive.

6. **Draft data pack**: A draft of the figures the Form 5500 needs goes to the plan administrator or your firm for review before EFAST2 filing.

## Common problems we fix

| The problem | How we fix it |
| --- | --- |
| Census does not match the payroll register | We tie both to the recordkeeper by participant and return an exception list the sponsor can fix before fieldwork. |
| Audit request list rebuilt from scratch each year | We keep a plan-specific list and carry it forward with status columns. |
| Deposit dates taken from investment dates | We test against the date funds left the employer's account, using payroll and bank evidence. |
| Form 5500 data assembled the week of the deadline | We tie the figures to the trust statement earlier in the year and hand the administrator a reviewed pack. |
| Loan and distribution exceptions found only in the auditor's sample | We test the full population and flag exceptions in advance. |

Pricing: Pricing is per plan, based on participant count, payroll sources and workpapers requested, and quoted in writing after we see sample data. Recurring capacity for firms with many plans is scoped as an ongoing engagement; see [/us/pricing](/us/pricing). ([See pricing](https://finbryn.com/us/pricing))

## Glossary

- **Form 5500**: The annual return and report that most employee benefit plans file with the Department of Labor through the EFAST2 system.

- **EFAST2**: The Department of Labor's electronic filing system for the Form 5500 series.

- **Plan administrator**: The person or entity named in the plan document who is responsible for the plan and signs the Form 5500.

- **PBC list**: Prepared by client list: the documents and data an auditor asks the plan sponsor to provide.

- **Form 5558**: The IRS form used to request an extension of time to file the Form 5500, normally by the original due date.

## Frequently asked questions: Employee benefit plan audit and Form 5500 support

**Q: Who signs and files the Form 5500?**

A: The plan administrator signs it and files it electronically on EFAST2, directly or through a firm acting for them. For a calendar-year plan the due date is July 31, or October 15 with a timely Form 5558. We prepare a draft data pack and never file.

**Q: Which plans need an audit?**

A: Generally plans with 100 or more participants at the start of the plan year (for 401(k) and other defined contribution plans, participants with account balances, the count used since 2023 plan years), under the counting rules in the Form 5500 instructions. A plan that filed as a small plan the year before can stay small until it passes 120. Your auditor confirms the count.

**Q: Do you write the audit report or review the plan's financial statements?**

A: No. The independent auditor who signs the report owns the audit and every conclusion in it. We prepare request lists, tie-outs and testing workpapers for that auditor to review.

**Q: What is the deadline for depositing employee deferrals?**

A: Under 29 CFR 2510.3-102, as soon as they can reasonably be segregated, and no later than the 15th business day of the following month. Plans under 100 participants have a seven business day safe harbor. We test your pay dates against both, checked 2026-10-09.

**Q: Do you handle Schedule SB for defined benefit plans?**

A: No. Actuarial schedules need a credentialed actuary, so defined benefit work is excluded. We cover defined contribution plans and the participant and financial data around the filing.

**Q: Is our client's data protected?**

A: We ask only for the fields each test needs, receive them over your secure channel, and follow the consent rule in IRC section 7216 before return information is shared. See [review support](/services/for-accounting-firms/review-support) for how we work inside your reviewer workflow.

**Q: Who signs and files the Form 5500?**

A: The plan administrator signs and files it electronically on EFAST2. We prepare the data pack and schedules for the administrator or the firm that supports it, and we never file for them.

**Q: Do you issue the plan audit report?**

A: No. The independent auditor who signs the report owns every conclusion. We prepare request lists, tie-outs and testing workpapers that the audit team reviews and re-performs as it sees fit.

**Q: What about Schedule SB and other actuarial schedules?**

A: Defined benefit schedules are excluded because they need a credentialed actuary. This service covers defined contribution plans and the financial and participant data around the filing.

**Q: Is return information shared with you?**

A: Only after consent. The signing preparer obtains the client's written consent before return information is shared with a service provider, consistent with IRC section 7216, and we treat Form 5500 data the same way.

Related services:
- [Review support](https://finbryn.com/us/services/for-accounting-firms/review-support)
- [PBC list management](https://finbryn.com/us/services/audit-compliance-support/pbc-lists)
- [Working paper preparation](https://finbryn.com/us/services/audit-compliance-support/working-papers)
- [Busy season tax prep support](https://finbryn.com/us/services/for-accounting-firms/busy-season-tax-prep-support)

Industries:
- [Professional services](https://finbryn.com/us/industries/professional-services)
- [Medical and dental practices](https://finbryn.com/us/industries/medical-dental)

## Sources

1. [U.S. Department of Labor, EFAST2 electronic filing system for the Form 5500 series](https://www.efast.dol.gov/) (2026-10-09)
2. [U.S. Department of Labor, Form 5500 Series (instructions and filing requirements)](https://www.dol.gov/agencies/ebsa/employers-and-advisers/plan-administration-and-compliance/reporting-and-filing/form-5500) (2026-10-09)
3. [29 CFR 2510.3-102, Definition of plan assets: participant contributions](https://www.ecfr.gov/current/title-29/subtitle-B/chapter-XXV/subchapter-F/part-2510/section-2510.3-102) (2026-10-09)
4. [AICPA Employee Benefit Plan Audit Quality Center](https://www.aicpa-cima.com/resources/landing/employee-benefit-plan-audit-quality-center) (2026-10-09)
5. [IRS, About Form 5558, Application for Extension of Time to File Certain Employee Plan Returns](https://www.irs.gov/forms-pubs/about-form-5558) (2026-10-09)

Reviewed October 2026

[All services in For accounting and tax firms](https://finbryn.com/us/services/for-accounting-firms)

## Contact
- Phone: +1 (312) 313-7376
- Email: hello@finbryn.com
- Booking page: https://finbryn.com/us/book