Mantech International Corporation 401(k) Plan: Login, Facts & Contact Information

Mantech International Corporation 401(k) Plan Facts

Plan name
MANTECH INTERNATIONAL 401(K) PLAN
Plan type
401(k) with employer contributions and profit sharing
Plan sponsor
MANTECH INTERNATIONAL CORPORATION
Participants
15,538 (8,433 active employees)
Former employees with a balance
6,483
Plan assets
$1,704,591,803 at Dec 31, 2024
Average account balance
$115,998 across 14,695 accounts
Employer contributions
$41,160,036 in plan year 2024 (25% of all contributions)
Recordkeeper
Fidelity Investments Institutional
Plan year
Jan 1, 2024 – Dec 31, 2024
Plan established
Jun 1, 1978
✓ Employer contributions— Automatic enrollment✓ Default investment for undecided participants✓ Participants choose their own investments✓ Self-directed brokerage window✓ Profit sharing— Company stock (ESOP)

Source: Form 5500 for plan year 2024 (Jan 1, 2024 – Dec 31, 2024), filed Oct 15, 2025. Public filing with the U.S. Department of Labor.

Money in and out in plan year 2024

  • $164.1 million went into the plan in contributions, $41.2 million of it from the employer (25%).
  • $231.3 million was paid out to participants.
  • Investment and other income added $235.1 million.
  • Administrative expenses were $666,747, about $45 per account.

How the Mantech International Corporation 401(k) changed, 2019–2024

Plan yearParticipantsPlan assetsEmployer contributionsBenefits paid
201912,313$1.04 billion$26.8 million$109.7 million
202013,877$1.26 billion$31.8 million$106.2 million
202114,286$1.46 billion$39.8 million$135.3 million
202217,073$1.26 billion$42.2 million$169.3 million
202315,983$1.54 billion$42.1 million$160.2 million
202415,538$1.70 billion$41.2 million$231.3 million

Mantech International Corporation 401(k) Contact Information

Phone
703-218-6000
Mailing address
2251 CORPORATE PARK DRIVE, HERNDON VA 20171
Plan sponsor
MANTECH INTERNATIONAL CORPORATION
Employer identification number (EIN)
22-1852179
Plan number
002

Questions about the Mantech International Corporation 401(k)

Does Mantech International Corporation contribute to the 401(k)?

Yes. The plan reports an employer contribution arrangement. In plan year 2024 the employer contributed $41.2 million, 25% of all contributions.

Does the Mantech International Corporation 401(k) have automatic enrollment?

No. The plan does not report automatic enrollment; employees enroll themselves.

How many people are in the Mantech International Corporation 401(k) plan?

15,538 participants at the start of plan year 2024, 8,433 of them active employees, and 6,483 former employees who still had money in the plan.

What is the average 401(k) balance at Mantech International Corporation?

About $115,998 per account: $1.70 billion in plan assets across 14,695 accounts with a balance at the end of plan year 2024.

Who manages the Mantech International Corporation 401(k) accounts?

Fidelity NetBenefits (listed on the filing as FIDELITY INVESTMENTS INSTITUTIONAL) is the plan's recordkeeper, which is where participants log in to see their balance.

I no longer work at Mantech International Corporation. How do I access my 401(k)?

Your account stays with Fidelity NetBenefits after you leave, so you can log in with the same credentials. If your balance was small, the plan may have rolled it into an IRA in your name. If you can't find it, Beagle can locate it for you.

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