These Oslo-based companies primarily offer consulting services across various sectors. While some are large, established firms like Multiconsult, founded in 1908, and BDO Norge, founded in 1913, there is also a significant presence of younger companies, such as AIDER (2019) and NoA - The North Alliance (2014).
The companies listed include Multiconsult, which provides consulting, engineering, and design services, and Bouvet ASA, a Scandinavian company offering technology, communication, and management services. Zalaris specializes in HR and payroll administration solutions, and AGR is an engineering consultancy and software provider for energy solutions. A notable pattern is the strong representation of IT services and IT consulting firms, with Bouvet ASA, Advania Norge, NoA - The North Alliance, Itera, and Bekk all operating in this field.
| # | Company | Employees | |||
|---|---|---|---|---|---|
| 1 |
Multiconsultmulticonsult.no
Multiconsult offers a wide range of consulting, engineering, and design services in various sectors, with a focus on meeting customer expectations and achieving satisfaction |
3,018 | |||
| 2 |
Bouvet ASAbouvet.no
Leading Scandinavian consulting company providing technology, communication, and management services. Offers development and advisory services to public and private sector clients. |
2,325 | |||
| 3 |
Zalariszalaris.com
Providing HR and payroll administration solutions, empowering clients with valuable information to invest in their people, fostering team spirit and achieving high results |
1,822 | |||
| 4 |
PwC Norwaypwc.no
A leading global professional services firm with deep expertise in auditing, advisory, and legal services, operating in 155 countries worldwide |
1,802 | |||
| 5 | 1,596 | ||||
| 6 | 1,540 | ||||
| 7 |
KPMG Norwaykpmg.com
Providing audit, consulting, legal services with focus on cybersecurity, sustainability, technology, and future-oriented business solutions for clients. |
1,514 | |||
| 8 | 1,471 | ||||
| 9 |
Rystad Energyrystadenergy.com
An independent advisory and research firm providing data and insights for decision-making in global energy markets, spanning oil, gas, renewables, and more |
939 | |||
| 10 |
Advania Norgeadvania.no
A Northern European IT-services company with over 3,500 employees, helping customers improve performance through innovative use of IT platforms |
699 | |||
| 11 |
NoA - The North Alliancethenorthalliance.com
A Nordic-based creative and tech group with over 1200 experts focused on driving customer-driven growth in Sweden, Norway, Denmark, Finland, and Poland |
623 | |||
| 12 | 618 | ||||
| 13 | 604 | ||||
| 14 | 533 | ||||
| 15 |
NGI - Norwegian Geotechnical Institutengi.no
NGI is an international center for research and consultancy in engineering-related geosciences, specializing in finding sustainable solutions for infrastructure and environmental challenges worldwide |
480 | |||
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| 16 |
Webstepwebstep.no
A profitable technology and consulting firm with 400+ IT experts, providing uncomplicated solutions to complex problems for customers across industries |
430 | |||
| 17 |
WSP i Norgewsp.com
A leading company in project management, providing services to public and private sectors in industries such as construction, transportation, energy, and industrial sectors |
416 | |||
| 18 | 403 | ||||
| 19 | 358 | ||||
| 20 |
Computas AScomputas.com
Nordic provider of IT solutions and consulting, specializing in cloud solutions, AI, and machine learning, with expertise in system development and digitization processes |
340 | |||
| 21 |
VIEW Group Norgeviewgroup.no
VIEW Ledger is a technology-driven company providing automated systems and outsourcing services for finance and accounting processes since 2004 Serving multinational corporations and small businesses |
331 | |||
| 22 |
Eiendomshuset Malling & Comalling.no
This company is a prominent provider of commercial real estate services in Norway, managing a large portfolio and facilitating significant transactions |
329 | |||
| 23 |
RSM Norgersm.global
A medium-sized audit and advisory firm in Norway, specializing in audit, tax, transactions, and providing tailored services across various industries |
326 | |||
| 24 |
The Cloud People Globalthecloudpeople.com
Global ServiceNow Elite partner with expertise in advising, implementing, and managing ServiceNow solutions for maximum value and customer satisfaction |
316 | |||
| 25 | 306 | ||||
| 26 |
Arribatec Grouparribatec.com
Global provider of digital business solutions, focusing on ERP, system integration, and CPM Emphasizing innovative use of IT for competitive advantage |
294 | |||
| 27 |
Nord Poolnordpoolgroup.com
Europe's leading power market offering efficient trading, clearing, and settlement services across multiple countries, with 30 years of experience in the industry |
186 | |||
| 28 | 56 | ||||
| 29 |
Clave Consultingclave.no
IT consulting firm offering services in user experience, software development, advisory, and architecture, dedicated to providing the best advice and creating new opportunities for clients |
38 | |||
| 30 |
Tellmann Executive Advisors AStellmann.no
A leading independent advisory firm specializing in ERP renewal, business solutions, and IT organization, driving digital transformation for businesses of all sizes and industries |
34 | |||
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How this list is built
Every company on this list has a Tamtam company profile. The industry is the one the company gives on LinkedIn; categories such as SaaS or fintech are classified by Tamtam's AI from the company's website and LinkedIn page; and the headquarters city must match the company's own address. Companies are ranked by the number of employees on LinkedIn, and the list is refreshed every night. Classifications can be wrong, so treat the list as a starting point rather than an official ranking. Last updated Nov 11, 2026.
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