What Castellum does

Castellum is one of the largest listed commercial real estate companies in Sweden, headquartered in Göteborg and operating a portfolio of 654 properties (valued at SEK 136.9 billion at year-end 2025) across more than 20 Swedish cities, with select logistics operations in Denmark and Finland covering 1.5 million square meters. The company was founded in 1993, is listed on the Stockholm Stock Exchange and NYSE American (ticker CTM), and is led by CEO Pål Ahlsén under a "Back to Basics" strategy targeting a 10% return on equity. Its largest disclosed shareholder is Akelius Apartments (Roger Akelius).

The company's core offerings fall into three product lines: (1) office solutions spanning customized build-to-suit offices, key-ready offices, and coworking/office hotels with lease terms from one day to multiple years; (2) logistics and industrial solutions including volume warehouses, distribution terminals, last-mile facilities, and business premises across Sweden, Denmark, and Finland; and (3) new construction (nyproduktion) of sustainably certified buildings. Supporting these are advisory services such as a free GDPR-secure office survey (Kontorsenkäten), workplace strategy consulting, green lease agreements, real-time electricity monitoring, the "100 på sol" solar program (130 installations, 17.2 GWh annually), and a power-strategy partnership with five Swedish energy companies. Castellum also operates 27 active new-construction projects and a 1,000+ EV-charging-point network across its portfolio.

Castellum makes money primarily through long-term commercial rental income from office, logistics, and industrial tenants across Sweden, with named enterprise customers including Ericsson (71,000 sqm Hagastaden campus), PostNord, Lindab, Meca, Bravida, Ahlsell, Hedin Bil, Porsche Center Göteborg, and Budbee. Reported income from property management was SEK 4.61 billion for full year 2025 (down 4.4% year-over-year) and Q1 2026 NOI declined a further 3% year-over-year. Go-to-market is enterprise field sales supported by a digital property-listing portal (845 active listings), dedicated local "house teams" at every property, and free advisory content that generates top-of-funnel demand. The 2026 capital-recycling program — including the SEK 13.3 billion Skåne portfolio sale to Wihlborgs, SEK 5.6 billion social-infrastructure sale to AP7, and SEK 256 million Linköping divestiture — is reshaping the portfolio toward higher-return assets, with proceeds largely returned to shareholders via buybacks and dividends.

Name

Castellum

Legal name

Castellum AB (publ)

Website

https://castellum.se

Company type

Public

Founded year

1993

Operating status

Operating

Headcount range

51–100 employees

Short description

Castellum is one of Sweden's largest listed commercial real estate companies, operating a 654-property portfolio (SEK 136.9 billion) across Sweden plus select logistics in Denmark and Finland. It develops, leases, and manages office, logistics, industrial, and retail space for enterprise and mid-market tenants under a sustainability-led strategy.

Ownership category

akta.pro rank

Product category

Commercial Real Estate

NAICS

Lessors of Nonresidential Buildings (except Miniwarehouses) (531120)

SIC

Real Estate Operators (No Developers) & Lessors (6510)

akta.pro primary industry

Office Property Management (BPAJAGAA)

Keywords

• Commercial real estate leasing
• Office property rental
• Logistics warehousing
• Sustainable property management
• Commercial property development

Headquarters

HQ city

Göteborg

HQ country

Sweden

HQ region

Europe

Offices11 records

Markets served

GTM type

B2B

Offering type

Services

Cost components

Personnel, Operations, Infrastructure, Supply Chain, Marketing or Sales, Technology or R&D

Revenue model

1. Commercial Property Rental Income: Castellum derives the vast majority of its revenue from long-term commercial leases with tenants across office, logistics/warehouse, and light industrial space types. The company emphasizes long-term lease relationships and had income from property management of SEK 4.61 billion for full year 2025.

Pricing tiers

Go-to-market motion1 record

Distribution channels4 records

Marketing channels6 records

Core offering

Castellum owns, develops, and leases 654 commercial properties across Sweden spanning office, logistics/warehouse, and light industrial space, with selected presence in Denmark and Finland covering 1.5 million sqm of logistics space. The company generates recurring rental income from long-term leases with enterprise tenants such as Ericsson, PostNord, and Bravida, while also providing build-to-suit new construction, coworking, green lease frameworks, and sustainability services including real-time energy monitoring and solar energy under its '100 på sol' program.

Product overview

Castellum is a Nordic commercial real estate company offering a comprehensive portfolio of property solutions. The core offering consists of three main product categories: (1) Office Solutions including Customized Offices, Key-Ready Offices, and Coworking/Office Hotels, (2) Logistics/Warehouse Solutions encompassing Volume Warehouses and Terminals, Last Mile Logistics, and Business Premises, and (3) New Construction Development. These are supported by a range of advisory services including Office Surveys, Workplace Strategy Consulting, Green Lease Agreements, Sustainability Consulting, Real-Time Electricity Monitoring, and the Power Strategy initiative. The company also offers specialized outdoor office spaces and comprehensive tenant services including fault reporting and property maintenance. Castellum positions itself as 'Nordens mest hållbara fastighetsbolag' (the Nordic region's most sustainable property company), integrating sustainability across all offerings.

Differentiator

Problem solved

Functional benefit

Products and services

• Customized Offices (Skräddarsydda kontor) Tailored, long-term office leasing solutions where Castellum assesses needs, finds a location, and adapts the space to optimize for the tenant's business. Targeted at enterprises seeking bespoke headquarters.
• Key-Ready Offices (Nyckelfärdiga kontor) Fully furnished, move-in-ready offices or office hotels with short agreement terms from 3 months, designed for tenants who want plug-and-play space without the hassle of fit-outs.
• Coworking and Office Hotels Flexible shared workspace with representative offices, meeting rooms, reception, and services, with agreements starting from 1 day. Targets SMEs, startups, and project teams.
• Volume Warehouses and Terminals Large distribution centers and terminals placed strategically to optimize freight flows and reduce environmental impact. Targeted at logistics operators, postal services, and e-commerce fulfillment firms.
• Last Mile Logistics Properties Strategically placed last-mile, warehouse, retail, and distribution centers for the final step of bringing goods from warehouses to end consumers across Sweden, Denmark, and Finland.
• Business Premises (Verksamhetslokaler) Customized premises combining industrial, production, warehouse, and office or retail space, offered across major growth cities in Sweden for manufacturers, automotive dealers, and industrial operators.
• New Construction (Nyproduktion) Build-to-suit development of new properties and major renovations tailored to customer needs, including custom-built corporate HQs, dealerships, and logistics facilities, all sustainability-certified.
• Green Lease Agreements (Grönt hyresavtal) Collaborative lease framework between Castellum and tenants to jointly reduce the environmental impact of premises, including shared sustainability targets, joint monitoring, and access to green electricity via the Vattenfall partnership.
• Real-Time Electricity Monitoring Real-time electricity metering service giving tenants full visibility into their energy consumption, with potential to reduce electricity usage by up to 30%.
• Workplace Strategy Consulting Advisory service that maps customer workspace needs and defines the strategic direction for office and workplace optimization projects.

Quantifiable outcome

• Energy consumption 50% below industry average across Castellum's property portfolio
• +4 more outcomes

Named customers14 records

Segments4 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

Three partnerships are on record, tiered core, major and strategic.

• VattenfallcoreStrategic or Co-development PartnerStrategic partnership where Castellum and Vattenfall jointly offer green electricity contracts to Castellum's tenants. This enables tenants to switch to renewable energy through an advantageous deal negotiated by Castellum, supporting the company's green lease framework and sustainability strategy.
• ColliersmajorImplementation/ SI/ Consulting PartnerColliers acted as sell-side advisor to Castellum on the landmark SEK 5.6 billion divestiture of a social infrastructure portfolio (nine properties) to AP7. This was one of three Nordic real estate transactions totaling nearly SEK 16 billion that Colliers advised on in early 2026.
• Five Regional Energy Companies (effektstrategin)strategicStrategic or Co-development PartnerCastellum partnered with five Swedish regional energy companies (including Öresundskraft) on a collaborative 'effektstrategi' (power/effect strategy) to transform buildings into active power resources that reduce load on the strained national electricity grid, addressing Sweden's power shortage crisis.

Scale indicators14 records

Recent moves11 records

Expansion highlights6 records

Direct peers

• Vasakronan: Sweden's largest property company, focused on office, retail, and logistics properties in Swedish prime locations. Vasakronan directly competes with Castellum in the Swedish commercial property market with similar sustainability focus and institutional-grade tenants.
• Wihlborgs: Swedish commercial property company specializing in office and logistics properties in the Öresund region. Wihlborgs recently acquired Castellum's entire Skåne portfolio for SEK 13.3 billion in June 2026, establishing them as a direct competitor with overlapping product offerings and Swedish geography.
• Fabege: Swedish commercial property company focused on office and urban development in the Stockholm region. Fabege directly competes with Castellum in the prime Stockholm office market with similar institutional client base and sustainability positioning.
• Hufvudstaden: Swedish premium commercial property company focused on prime office and retail properties in Stockholm and Gothenburg. Hufvudstaden competes with Castellum in the high-end Swedish office segment with similar institutional clientele.
• Balder: Swedish real estate company with a diversified portfolio of residential, commercial, office, and logistics properties across the Nordics. Balder directly competes with Castellum in the Swedish commercial property market with overlapping geographic focus.
• Kungsleden: Swedish commercial property company with office, industrial, and logistics properties. Kungsleden competes with Castellum across Sweden and is now part of Castellum's broader corporate ecosystem per Castellum's investor relations page.
• Wallenstam: Swedish real estate company focused on residential and commercial properties in Stockholm and Gothenburg. Wallenstam competes with Castellum in the Swedish commercial real estate market with similar Swedish geographic focus.

Broad incumbents

• Stena Fastigheter: Swedish real estate company with a large portfolio of residential and commercial properties. Stena Fastigheter is a broader incumbent in Swedish real estate, competing with Castellum in commercial property while having greater residential exposure.
• Skanska: Major Swedish construction and real estate development company. While primarily a developer rather than long-term owner like Castellum, Skanska competes in commercial property development in Sweden and across the Nordics.

Regional players

• Sveafastigheter: Swedish residential and commercial property investor. Sveafastigheter operates in the broader Swedish real estate market with some commercial exposure, providing a smaller-scale peer comparison for Castellum's commercial portfolio.

Market position

Strengths5 records

Weaknesses5 records

Competitive moat5 records

Key risks6 records

Key highlights6 records

Customer concentration

• Facebooksv-se.facebook.com/castellumfastigheter
• LinkedInse.linkedin.com/company/castellum-ab
• Instagraminstagram.com/castellum_ab
• Xx.com/castellum_ab

Compliance5 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles2 records

Subsidiaries1 record

Funding overview

Funding rounds1 record

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A2 records

Investments1 record

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Castellum