Multiple plan years M sponsor index DOL Form 5500

Plans by Sponsor: M

ERISA Form 5500 plan record drawn from DOL EBSA, verify with linked source filings below.

1,003 retirement plans with sponsors starting with "M"

How can I browse retirement plans by sponsor?

This letter index groups 1,003 retirement plans whose sponsor name begins with the letter "M". The full browse index covers 16,325 plans across all 26 letters of the alphabet. Results are paginated 50 per page, and you are currently viewing page 3 of 21. Each listing links to a detail page with the plan's Form 5500 fields, plan type, total assets, participant count, sponsor EIN, state of record, and filing status for that plan's most recently filed plan year (listings on this index span multiple plan years, sortable below).

Sort controls above let you reorder the list by sponsor name (default alphabetical), participant count (largest first), or plan year. The participant column shows total covered workers, a mix of active employees, separated employees with remaining balances, and retirees receiving benefits. Sponsors are listed as they appear on the Form 5500 filing, which may differ from the public-facing corporate brand; a single holding company can sponsor multiple plans, and large employers may also appear under subsidiary names.

All data on this page comes from U.S. Department of Labor Form 5500 annual returns released through EFAST2. The dataset covers plans with 100+ participants plus smaller plans that file voluntarily. Figures reflect a single plan-year snapshot and fluctuate with market performance, contributions, and benefit payouts. This browse index is informational only, summarizing public regulatory filings for research and educational purposes, and is not retirement, tax, legal, or financial advice. Before relying on any figure to evaluate an employer's plan or make retirement decisions, verify the underlying filing directly on EFAST2 and consult a qualified professional.

Showing 101–150 of 1,003

Plan Participants
Mankato Clinic, Ltd. 401(k) Profit Sharing Plan
Mankato Clinic Ltd
857
Mrci 403(b) Plan
Mankato Rehabilitation Center, Inc.
1,436
M&h Partners in Wealth Savings Plan
Mann & Hummel Filtration Technology Group, Inc.
2,341
Mann+Hummel 401(k) Plan
Mann+Hummel Filtration Technology US LLC
4,856
Manna Development Group, LLC 401(k) Plan
Manna Development Group, LLC
2,295
Manning & Napier Advisors, LLC 401(k) and Profit Sharing Plan
Manning & Napier Advisors, LLC
325
Mannington 401(k) Retirement Savings Plan
Mannington Mills, Inc.
2,022
Manos Home Care Employee Stock Ownership Plan
Manos Home Care
2,232
Manpower Temporary Services 401(k) Plan
Manpower Temporary Services
1,444
Manpowergroup 401(k) Savings Plan
Manpowergroup Inc.
32,496
Retirement Savings Plus
Manroland Goss Web Systems Americas LLC
106
Manson Construction Co. Non-Craft Retirement Plan
Manson Construction Co.
281
Manson Construction Co. Non-Craft Employee Stock Ownership Plan
Manson Construction Holding Company
291
Mantech International 401(k) Plan
Mantech International Corporation
9,017
M&t Bank Corporation Pension Plan
Manufacturers and Traders Trust Co
3,825
M & T Bank Corporation Retirement Savings Plan
Manufacturers and Traders Trust Co.
22,161
Map Communications Holdings, Inc. 401(k) Employees' Stock Ownership Plan
Map Communications Holdings, Inc.
2,110
Mapa Operating, LLC 401(k) Plan for Non-Union Employees and Union Employees
Mapa Operating, LLC
1,452
Mapco 401(k) Plan
Mapco Express, Inc.
2,399
Mapei Corporation 401(k) Plan
Mapei Corporation
1,420
Mapfre U.S.a. Corp. Profit Sharing & 401(k) Savings Plan
Mapfre U.S.a. Corp.
2,043
Maplebear Inc. D/B/a Instacart Retirement Plan
Maplebear Inc. D/B/a Instacart
3,246
Maplewood Senior Living Retirement Plan
Maplewood Senior Living, LLC
1,438
Mar-Jac Poultry, Inc. 401(k) and Profit Sharing Plan
Mar-Jac Poultry, Inc.
2,361
Marathon Cheese Employee's 401(k) Retirement Plan
Marathon Cheese Corporation
2,243
Marathon Health, LLC. 401(k) Plan
Marathon Health, LLC.
1,420
Retirement Plan of Marathon Oil Company
Marathon Oil Company
1,273
Marathon Oil Company Thrift Plan
Marathon Oil Company
1,279
Marathon Petroleum Retirement Plan
Marathon Petroleum Company LP
17,916
Speedway Retirement Plan
Marathon Petroleum Company LP
63
Marathon Petroleum Thrift Plan
Marathon Petroleum Company LP
18,199
Marcal Paper Non-Union 401(k) Plan
Marcal Manufacturing, LLC
1,031
Marco Technologies, LLC 401(k) Plan
Marco, Inc.
1,177
Marcone Appliance Parts Center 401(k) Profit Sharing Plan
Marcone Appliance Parts Co.
1,992
Marcum Advisory Group, LLC 401(k) Plan
Marcum Advisory Group, LLC
3,682
Marcum LLP 401(k) Plan
Marcum LLP
3,578
Marek Brothers Family of Companies Profit Sharing Plan & Trust
Marek Shared Services LLC
1,311
Marel USA 401(k) Retirement Plan
Marel Inc.
746
Marelli North America, Inc. 401(k) Retirement Plan
Marelli North America, Inc.
2,773
Darcars Employees 401(k) Plan
Mariam, Inc. Dba Darcars
1,418
Mariani Enterprises 401(k) Savings Plan
Mariani Enterprises LLC
2,377
Memorial Health System Hospitals Defined Contribution Plan
Marietta Memorial Hospital
2,062
Retirement Plus of Memorial Health System Hospitals
Marietta Memorial Hospital
3,085
Marin General Hospital 403(b) Retirement Plan
Marin General Hospital
1,869
Marine Spill Response Corporation 401(k) Profit Sharing Thrift Savings Plan
Marine Spill Response Corporation
354
Marinemax, Inc. 401(k) Profit Sharing Plan
Marinemax, Inc.
3,313
Mariner Finance LLC 401(k) Plan
Mariner Finance, LLC
2,134
Mariner Savings Plan
Mariner Health Care
4,375
Mariner Wealth Advisors, LLC 401(k) Plan
Mariner Wealth Advisors, LLC
1,563
Marin General Hospital Retirement Plan
Marinhealth Medical Center
1,861
Data sourced from U.S. Department of Labor Form 5500 filings (EBSA). See our methodology for details.

Why Form 5500 Data Matters for Retirement Planning

Form 5500 is the annual return that virtually every private-sector retirement plan in the United States files with the Department of Labor. The filing covers funding, participant counts, plan investments, fees, service providers, and corrective contributions. Because the data is collected for regulatory oversight rather than marketing, it is one of the most consistent windows into the retirement economy: the same questions are asked of plans across all industries and all states, year after year. That consistency makes it possible to compare plans, sponsors, and markets on equal footing, a kind of comparability that voluntary survey data and vendor brochures cannot provide.

PlainRetire reorganizes the Form 5500 universe so a participant, employer, or analyst can ask everyday questions of the dataset without reading thousands of pages of agency documentation. Browsing by state surfaces concentration patterns: where pension assets sit, which states host the largest 401(k) sponsors, where retirement coverage trails the national average. Browsing by industry reveals the structural difference between sectors that historically relied on defined-benefit pensions and sectors that adopted defined-contribution plans early. Browsing by plan size highlights both the largest sponsors, typically Fortune 500 employers and multi-employer Taft–Hartley funds, and the long tail of small plans that collectively cover millions of workers.

What This Hub Page Aggregates

Each hub page on PlainRetire is a navigable index into the underlying database. The page shows summary counts, the most recent Form 5500 vintage, and direct links to individual plan detail pages. Detail pages carry the canonical filings, schedules where applicable, and audit trail back to the DOL's EFAST2 disclosure portal. Where the underlying dataset supports it, hub pages also expose key aggregates: total participant counts, aggregate assets, plan-type breakdowns (401(k), pension, profit-sharing, ESOP), and changes over the most recent reporting period.

Plan data is updated as DOL releases new annual Form 5500 datasets. Filings have a roughly seven-month lag from plan year end, so the most recent vintage typically reflects the previous full calendar year. This lag is inherent to the disclosure regime, plans are given time to gather audit reports and service-provider statements, and PlainRetire reflects the timing transparently rather than backfilling estimates.

Reading the Data With Appropriate Caveats

Aggregate numbers are useful for trend-spotting and structural comparison; they are less useful for decisions about a specific plan. The participant count for a state, for instance, includes both very large plans (which dominate the total) and very small plans (which influence median but not mean). When evaluating a specific employer's plan, drill into the plan detail page and consider plan-type, asset-mix, fee structure, and audit history, these details are flattened in any hub-level aggregate. Where regulatory updates change the categorization of a plan, PlainRetire preserves the historical filing alongside the most recent one so longitudinal analyses remain valid.