Mainstay Maritime
Mainstay Maritime operates a Jones Act-compliant fleet of 23 U.S.-flagged vessels providing bulk and liquid freight shipping on the Great Lakes for enterprise industrial customers in manufacturing, infrastructure, and food. It is privately held by Duration Capital Partners.
- Company typePrivate
- Founded1907
- HeadquartersWilliamsville, United States
- Headcount1,001–5,000
- GTM typeB2B
- OfferingServices
What Mainstay Maritime does
Mainstay Maritime operates a Jones Act-compliant fleet of 23 U.S.-flagged vessels providing bulk and liquid freight shipping services on the Great Lakes. The company is headquartered in Williamsville, New York, and operates through three core subsidiaries — American Steamship Company (founded 1907), Grand River Navigation (established 2000), and Andrie (acquired 2024) — supplemented by an in-house ship repair facility (Conneaut Creek Ship Repair, Ashtabula, OH) and warehouse operations in Toledo and Duluth. Its fleet spans Class I 1,000-foot self-unloading bulk carriers (up to 80,900 gross tons, 10,000 tons/hour unloading), Class II vessels (680'-815'), Class III vessels (630'-730') for tight waterways, tug-and-barge units, and liquid transporters (including the Endeavour/Karen at 51,942 barrels and Endurance at 36,475 barrels). Mainstay is described as the market leader for Jones Act shipping on the Great Lakes and the only carrier offering significant scale and vessel diversity in the region.
The company sells mission-critical marine logistics to enterprise industrial customers in North American manufacturing, infrastructure, and food/agriculture under multi-year contracts with negotiated, quote-based pricing not publicly disclosed. Revenue is generated through transportation of dry bulk and liquid commodities under subscription/recurring enterprise arrangements, with 1,436 annual vessel discharges and 337,000 miles traveled per season reported as operational benchmarks. The business carries 825+ employees including mariners and shoreside staff, and operates exclusively within the Great Lakes region under U.S. Jones Act regulations that restrict domestic waterborne commerce to U.S.-owned, U.S.-built, and U.S.-crewed vessels.
Mainstay is privately held by Duration Capital Partners, which completed its spin-out from Oaktree Capital in 2024 and acquired the predecessor Rand Logistics (previously NASDAQ-listed) through Oaktree's 2021-2023 take-private. In 2026 the company rebranded from Rand Logistics to Mainstay Maritime and divested its Canadian subsidiary Lower Lakes Towing (six vessels) to Algoma Central Corporation to focus exclusively on its U.S. Jones Act business. The strategic posture is a focused, PE-backed industrial shipping platform emphasizing scale, fleet diversity, and regulatory-protected domestic market access.
Mainstay Maritime firmographics
Firmographics- Name
- Mainstay Maritime
- Legal name
- Mainstay Maritime, Inc.
- Website
- https://mainstaymaritime.com
- Company type
- Private
- Founded year
- 1907
- Operating status
- Operating
- Headcount range
- 1,001–5,000 employees
- Short description
- Mainstay Maritime operates a Jones Act-compliant fleet of 23 U.S.-flagged vessels providing bulk and liquid freight shipping on the Great Lakes for enterprise industrial customers in manufacturing, infrastructure, and food. It is privately held by Duration Capital Partners.
- Ownership category
- akta.pro rank
Mainstay Maritime industry classification
Industry- Product category
- Marine Logistics Services
- NAICS
- Coastal and Great Lakes Freight Transportation (483113), Deep Sea, Coastal, and Great Lakes Water Transportation (48311), Marine Cargo Handling (488320)
- SIC
- Water Transportation (4400), Ship & Boat Building & Repairing (3730)
- akta.pro primary industry
- Bulk Dry Cargo Carriers (Capesize/Panamax/Supramax/Handysize) (TLADABAC)
- akta.pro secondary industries
- Liquid Bulk / Crude & Product Tanker Operators (VLCC/Suezmax/Aframax/MR) (TLADABAD), Commercial Ship Repair & Drydocking (TLAKAKAA)
Keywords
Where Mainstay Maritime is headquartered
LocationHeadquarters
- HQ city
- Williamsville
- HQ country
- United States
- HQ region
- North America
Offices6 records
Markets served
Mainstay Maritime business model
Business model- GTM type
- B2B
- Offering type
- Services
- Cost components
- Personnel, Operations, Infrastructure, Supply Chain, Technology or R&D
Revenue model
- Marine Bulk Freight Transportation: Transportation of dry bulk and liquid commodities across the Great Lakes via a fleet of 23 U.S.-flagged vessels, operating under Jones Act regulations for domestic waterborne commerce.
Pricing tiers
| Model | Billing | Price |
|---|---|---|
| Other | Multi-year contract | Contract-based enterprise pricing for bulk commodity transport |
Go-to-market motion1 record
Distribution channels1 record
Marketing channels1 record
Mainstay Maritime product offering
Product offeringCore offering
Mainstay Maritime provides marine bulk and liquid freight transportation services on the Great Lakes using a Jones Act-compliant fleet of 23 U.S.-flagged vessels, including self-unloading bulk carriers, tug and barge units, and liquid transporters. Operations span dry bulk and liquid cargo transport, in-house ship repair through Conneaut Creek Ship Repair, and warehouse and distribution services at Toledo and Duluth facilities, serving manufacturing, infrastructure, and food industry customers. The company is the market leader for Jones Act shipping on the Great Lakes.
Product overview
Mainstay Maritime operates a unified marine logistics platform serving the Great Lakes Region, comprising 23 U.S.-flagged vessels managed through three subsidiaries: American Steamship Company (founded 1907), Grand River Navigation (established 2000), and Andrie (acquired 2024). The fleet includes 16 self-unloading bulk carriers and 6 tug-barge units, organized into Class I (1,000-foot vessels up to 80,900 GT), Class II (680'-815' vessels for longer distances), and Class III (630'-730' vessels for tight waterways) segments, plus specialty liquid transporters. The company offers integrated services including marine cargo transport, ship repair (Conneaut Creek Ship Repair), and warehouse facilities (Toledo and Duluth). Operating exclusively under the U.S. Jones Act, Mainstay is the market leader for Jones Act shipping on the Great Lakes.
Differentiator
Problem solved
Functional benefit
Products and services
- Great Lakes Marine Bulk and Liquids Logistics Comprehensive supply chain solutions for marine bulk and liquids logistics in the Great Lakes Region, including dry bulk and liquid cargo transportation across 23 U.S.-flagged vessels, ship repair services, and warehouse and distribution facilities. Serves manufacturing, infrastructure, and food industry customers requiring reliable Jones Act-compliant domestic waterborne commerce.
- Dry Bulk Freight Transportation (Self-Unloading Bulk Carriers)
Quantifiable outcome
- 337,000 miles traveled annually across the Great Lakes
- +1 more outcomes
Companies that use Mainstay Maritime
Customer profileNamed customers3 records
Segments1 record
Ideal customer profiles1 record
Mainstay Maritime technology and API
TechnologyTechnology focussed No
API detail
- Has API
- No
- API docs
- API detail
Core technology
AI maturity
App detail
Feature3 records
Mainstay Maritime partnerships and signals
Strategic signalPartnerships
One partnership is on record.
- Algoma Central CorporationminorAlgoma Central Corporation agreed to purchase Mainstay Maritime's Canadian fleet and operating companies. The transaction involves six vessels and was expected to close in Q1 2026. This divestiture positioned Mainstay to focus on its core U.S. Jones Act business.
Scale indicators6 records
Recent moves8 records
Expansion highlights4 records
Mainstay Maritime competitors and assessment
Company assessmentDirect peers
- Algoma Central Corporation: Canadian-based Great Lakes marine transportation operator that just acquired Mainstay's Canadian fleet and operating companies (Lower Lakes Towing, six vessels, Q1 2026). Operates a comparable mix of self-unloading bulk carriers and tankers on the Great Lakes, with overlapping customer base in iron ore, grain, and salt transport.
- Interlake Steamship Company: One of the largest U.S.-flagged Great Lakes self-unloading bulk carrier operators, family-owned and based in Ohio. Directly competes with Mainstay's American Steamship Company subsidiary for iron ore, limestone, and coal tonnage, making it the closest head-to-head self-unloader fleet on the Great Lakes.
- The CSL Group (Canada Steamship Lines): Montreal-based global shipping company that is the largest operator of self-unloading vessels in the world, with a major Great Lakes presence. Competes with Mainstay for the same iron ore, coal, and limestone routes on the Great Lakes and shares the self-unloading vessel technology model.
Regional players
- Van Enkevort Tug & Barge: Family-owned Great Lakes tug and barge operator running self-unloading bulk carriers on U.S. and Canadian waters. Directly comparable to Mainstay's tug-barge segment and overlaps in limestone, iron ore, and construction aggregate customers on the upper Great Lakes.
- Great Lakes Dredge & Dock Corporation: Houston-based largest provider of dredging services in the U.S., with extensive Great Lakes operations. Adjacent peer as a marine services platform on the same waterways, though focused on dredging rather than cargo transport; shares the same regulatory and Jones Act constraints for U.S.-flagged operations.
Broad incumbents
- Kirby Corporation: Houston-based largest U.S. inland tank barge operator (~$3B revenue) with growing coastal and offshore operations. Comparable to Mainstay's liquid bulk business model (post-Andrie acquisition) and shares asset-heavy marine transportation economics, though Kirby operates primarily on U.S. rivers and coastal waterways rather than the Great Lakes.
Market position
Strengths5 records
Weaknesses5 records
Competitive moat5 records
Key risks6 records
Key highlights7 records
Customer concentration
Mainstay Maritime financial estimates
Financial estimateRevenue estimate
Valuation estimate
Mainstay Maritime leadership team
Management profileNumber of profiles
Profiles7 records
Mainstay Maritime subsidiaries and ownership
Company hierarchySubsidiaries4 records
Mainstay Maritime funding detail
Funding detailFunding overview
Funding rounds
Investors
Funding detail is available on the Subscription and Enterprise plan.Contact sales →
Mainstay Maritime M&A and investment
M&A and investmentM&A
Investments
M&A and investment is available on the Subscription and Enterprise plan.Contact sales →
Frequently asked questions about Mainstay Maritime
What does Mainstay Maritime do?
Mainstay Maritime provides marine bulk and liquid freight transportation services on the Great Lakes using a Jones Act-compliant fleet of 23 U.S.-flagged vessels, including self-unloading bulk carriers, tug and barge units, and liquid transporters. Operations span dry bulk and liquid cargo transport, in-house ship repair through Conneaut Creek Ship Repair, and warehouse and distribution services at Toledo and Duluth facilities, serving manufacturing, infrastructure, and food industry customers. The company is the market leader for Jones Act shipping on the Great Lakes.
Is Mainstay Maritime a public or private company?
Mainstay Maritime is a private company. It is classified as private equity controlled and is currently operating.
When was Mainstay Maritime founded?
Mainstay Maritime was founded in 1907. It employs 1,001 to 5,000 people.
Where is Mainstay Maritime based?
Mainstay Maritime is headquartered in Williamsville, United States, in the North America region.
How does Mainstay Maritime make money?
One revenue line is on record: marine Bulk Freight Transportation.
Who are Mainstay Maritime's main competitors?
Direct peers on record are Algoma Central Corporation, Interlake Steamship Company and The CSL Group (Canada Steamship Lines). Regional players are Van Enkevort Tug & Barge and Great Lakes Dredge & Dock Corporation. Kirby Corporation is listed as a broad incumbent.
Does Mainstay Maritime have an API?
No public API is recorded for Mainstay Maritime.
What industry is Mainstay Maritime in?
Mainstay Maritime's product category is Marine Logistics Services. Its primary akta.pro industry code is TLADABAC, Bulk Dry Cargo Carriers (Capesize/Panamax/Supramax/Handysize), with a secondary code of TLADABAD, Liquid Bulk / Crude & Product Tanker Operators (VLCC/Suezmax/Aframax/MR). Its NAICS code is 483113 and its SIC code is 4400.