401(k) · DOL Form 5500 · 2023

Northwestern Corporation 401(k) Plan

Data updated 2026-08-25

$463M
Total assets Above avg plan size
1,529
Participants Near avg headcount
97th
Percentile by assets National rank
$302,653
Avg per participant High balance/head
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Official DOL plan name: Northwestern Energy 401(k) Retirement Savings Plan · Sponsored by Northwestern Corporation · Montana · Utilities

$463M in assets, 1,529 participants

Northwestern Corporation's Northwestern Energy 401(k) Retirement Savings Plan reported $463M in total assets and 1,529 participants in its 2023 DOL Form 5500 filing, ranking in the 97th percentile by assets among filed plans. Figures are as reported by the plan sponsor to the Department of Labor, not audited or endorsed by PlainRetire.

  • #589 in Utilities (721 peers)

Coverage in Montana

Northwestern Energy 401(k) Retirement Savings Plan covers 1,529 participants in Montana, 5.6x the typical Montana plan (state average ~271 per filing). Assets: $463M.

#589
in Utilities (721 peers)
+14.1%
assets growth YoY
4.6×
vs typical plan assets (national mean)

Northwestern Energy 401(k) Retirement Savings Plan's outsized position by total assets

Northwestern Energy 401(k) Retirement Savings Plan vs every filed plan by assets

End-of-year total assets · plan year 2023 · DOL Form 5500

$462,756,735 Top 3% higher than 97% of 127,068 filed plans

This plan $0 $2,050,000,000 every filed plan with reported assets, bucketed by value

Dashed line + filled bar = this entry, among filed plans.

Source U.S. Department of Labor Form 5500 filings (EBSA) · plan year 2023

Northwestern Energy 401(k) Retirement Savings Plan's large-plan peer group by participant headcount

Plan-year 2023 Form 5500 filings with a reported participant count, partitioned by headcount band, not by assets. Northwestern Energy 401(k) Retirement Savings Plan lands in the large band (1,529 participants).

What changed between DOL Form 5500 filings

plan year 2022 → plan year 2023

  • Northwestern Energy 401(k) Retirement Savings Plan reported net income rose from -$88M in the plan year 2022 filing to $57M in the plan year 2023 filing.
  • Northwestern Energy 401(k) Retirement Savings Plan end-of-year assets rose from $406M in the plan year 2022 filing to $463M in the plan year 2023 filing.
  • Northwestern Energy 401(k) Retirement Savings Plan reported participants rose from 1,494 in the plan year 2022 filing to 1,529 in the plan year 2023 filing.

See the national 2022→2023 release diff →

Form 5500 schedule snapshot

Filing strip 460172280 · Northwestern Corporation PY 2023 · 401(k)

Northwestern Energy 401(k) Retirement Savings Plan · $463M · 1,529 · 97th

  • PART $463M
  • PART 1,529
  • PART 97th
  • PART 401(k)
  • PART near Day & Zimmermann Retirement Plan
  • PART ind #589

Stamps derive from this plan's Form 5500 line items (assets, participants, type, EIN, cohort placement) - not a quality rating of the sponsor. Read with Utilities retirement plans → · Plans in Montana →

Northwestern Energy 401(k) Retirement Savings Plan in the asset neighbourhood

Kutak Rock LLP 401(k) Profit Sharing PlanKutak Rock LLP 401(k) Profit…$463MPinnacle Financial Partners, Inc. 401(k) PlanPinnacle Financial Partners,…$463MDay & Zimmermann Retirement PlanDay & Zimmermann Retirement …$463MNorthwestern Energy 401(k) Retirement Savings PlanNorthwestern Energy 401(k) R…$463MVedder Price P.C. Profit Sharing and Retirement PlanVedder Price P.C. Profit Sha…$462M
End-of-year total assets ($M) among Northwestern Energy 401(k) Retirement Savings Plan and nearest nationwide 401(k) peers. Source: DOL Form 5500 plan year 2023.

Montana filing particulars

Total Assets (Beginning of Year)$406M
Net Assets (End of Year)$463M
Net Income$57M
Employer EIN460172280
Plan Effective Date1984-01-01
Filing StatusFILING RECEIVED

Sponsor Plan History (Northwestern Corporation)

Sponsor-wide plan assets over time

All Northwestern Corporation plans reported in each filing year

Latest sponsor-wide plan assets
$911M 6.581242375535956% vs 2022
2024 filing year
$840M$860M$880M$900M$920M 202220232024 $855M $911M ▲ +6.6%
Year Plans Participants Total Assets
2022 3 2,084 $855M
2023 3 2,047 $869M
2024 3 2,037 $911M

Nearby 401(k) Plans in Montana

Peer 401(k) plans, same state, same plan type, ranked by total assets.

Northwestern Energy 401(k) Retirement Savings Plan vs. nearby 401(k) plans in Montana, assets vs. participants Scatter plot of 6 data points. 10002000300040005000 400450500550 Total assets ($M) Participants Northwestern Energy 401(k) Retirement Savings Plan, Total assets ($M): 462.756735 · Participants: 1529Northwestern Energy 401(k) Retirement Savings PlanD.a. Davidson Companies Retirement Savings and Profit Sharing Plan, Total assets ($M): 543.142005 · Participants: 1580D.a. Davidson Companies Retirement Savings and Profit Sharing PlanGlacier Bancorp, Inc. Profit Sharing and 401(k) Plan, Total assets ($M): 484.798151 · Participants: 3264Glacier Bancorp, Inc. Profit Sharing and 401(k) PlanFirst Interstate Bancsystem, Inc. 401(k) Plan, Total assets ($M): 453.618257 · Participants: 3750First Interstate Bancsystem, Inc. 401(k) PlanLogan Health Retirement Savings Plan, Total assets ($M): 436.597451 · Participants: 4232Logan Health Retirement Savings PlanWashington Companies 401(k) Retirement Savings Plan, Total assets ($M): 417.849493 · Participants: 2114Washington Companies 401(k) Retirement Savings Plan
Northwestern Energy 401(k) Retirement Savings Plan vs. nearby 401(k) plans in Montana, assets vs. participants
Compare Northwestern Energy 401(k) Retirement Savings Plan side-by-side with 3 peers →

Northwestern Energy 401(k) Retirement Savings Plan's out-of-state 401(k) peers by assets and headcount

Outside Montana, the nearest 401(k) by assets is Day & Zimmermann Retirement Plan in PA ($463M); by covered participants it is Kipp Nyc 403(b) Retirement Plan in NY (1,529 participants). Same-state nearby plans are listed separately above.

Closest by plan assets

Nearest other-state filings by tot_assets_eoy ($463M here).

Similar participant headcount

Nearest other-state filings by covered participants (1,529 participants); asset peers above are excluded.

DOL Form 5500 plan year 2023. Asset totals can differ widely at the same headcount; neither axis is a quality rating.

Frequently Asked Questions

How did Northwestern Energy 401(k) Retirement Savings Plan assets move in 2023? ▼
Northwestern Energy 401(k) Retirement Savings Plan grew at a solid clip - up 14.1% during 2023, from $406M to $463M. Reported net income was $57M.
How have Northwestern Corporation plan assets changed over time? ▼
Across 3 plan years on file (2022-2024), Northwestern Corporation's sponsor-wide assets grew 6.6%, from $855M to $911M.
Where does Northwestern Energy 401(k) Retirement Savings Plan rank by assets among Form 5500 filers? ▼
Northwestern Energy 401(k) Retirement Savings Plan ranks in the 97th percentile by end-of-year assets among 127,072 plans that reported assets for plan year 2023 (in the top 5% of all filed plans by assets).
Which 401(k) plans are similar in size to Northwestern Energy 401(k) Retirement Savings Plan? ▼
Among 401(k) plans in other states, the closest by assets is Day & Zimmermann Retirement Plan in PA ($463M, 4,634 participants).
Which 401(k) plans cover a similar participant headcount to Northwestern Energy 401(k) Retirement Savings Plan? ▼
Among 401(k) plans in other states, the closest by covered participants is Kipp Nyc 403(b) Retirement Plan in NY (1,529 participants, $78M in assets).

Source: U.S. Department of Labor, Employee Benefits Security Administration (EBSA), Form 5500 public disclosure dataset. Plan year 2023.

Source: DOL EFAST2 filing system (efast.dol.gov) - original filing retrieval by EIN 460172280.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from U.S. Department of Labor Form 5500 filings (EBSA). See our methodology for details.