Top sustainability consultancies for mid-market companies

“Choosing the right sustainability consultancy means having ESG experts by your side who pushes you beyond compliance towards lasting impact.”

Why mid-market companies need specialised ESG consultancies

As the global focus on corporate responsibility intensifies in 2025, mid-market companies find themselves at a pivotal crossroads. Unlike larger corporations with dedicated ESG teams and abundant resources, these firms often grapple with complex sustainability demands while operating with leaner structures and tighter budgets. Yet, the pressure to deliver credible Environmental, Social, and Governance (ESG) performance is stronger than ever.

This dynamic makes specialised ESG consultancies crucial partners for mid-market firms seeking more than just compliance checklists. By offering agile, pragmatic, and cost-effective strategies tailored to the unique challenges of this segment, such consultancies unlock new pathways to long-term value creation, competitive differentiation, and resilient growth. Understanding why mid-market companies require focused ESG expertise is key to harnessing these opportunities and navigating the evolving sustainability landscape with confidence.

The growing importance of ESG for mid-market companies

ESG expectations have expanded beyond large corporations. Mid-market companies now face rising demands from investors, regulators, customers, and employees to demonstrate strong environmental, social, and governance performance. Despite often having fewer internal resources compared to large firms, mid-market businesses encounter complex sustainability challenges that require expert guidance to navigate efficiently.

Studies show that over 75% of mid-market businesses are actively embedding ESG metrics into their operations to meet rising investor, regulatory, and customer expectations (1). Furthermore, 62% of mid-market businesses believe sustainability is as important or more important than financial success (2). Additionally, 34% of mid-market companies have reduced net carbon emissions to zero or are currently acting to reduce their net carbon emissions to zero (3).

These statistics underscore the increasing recognition among mid-market companies of the importance of ESG factors in their operations and long-term success.

The difference in ESG strategy between medium and large organisations

Medium-sized companies usually operate with leaner sustainability teams and simpler management systems compared to large corporations. While large companies can invest heavily in dedicated ESG departments and sophisticated reporting infrastructures, mid-market firms need agile, scalable strategies that integrate ESG into core business functions without overwhelming resources. Reporting obligations and stakeholder demands also differ, requiring a tailored approach that balances ambition with practicality (2).

Why work with an ESG consultancy specialised in mid-market?

Consultancies specialised in mid-market companies understand the scale and resource limits unique to this segment. They provide cost-effective, flexible solutions designed to deliver impact without the complexity or cost suited for larger firms. Such experts appreciate mid-market growth ambitions and regulatory environments, focusing on pragmatic strategies that drive compliance, efficiency, and long-term value.

Key benefits specific to mid-market companies from ESG consultancies

Expert navigation of complex compliance landscapes

Objective gap analysis and actionable improvement plans

Efficient use of limited internal sustainability resources

Access to sector-specific best practices and benchmarking

Enhanced credibility with investors and stakeholders

Driving competitive advantage alongside regulatory compliance

Selecting the right consultant

Selecting the right ESG consultancy is a critical decision for mid-market companies aiming to build sustainable, resilient businesses. Here are five key factors to consider:

Strong partnerships: Ensure the consultancy has solid ties with leading ESG organisations and frameworks. For example, Nexio Projects is an EcoVadis strategic partner and a B Corp Way partner, reflecting close collaboration with globally recognised sustainability standards (EcoVadis and B Corp).
Proven track record: Look for consultants with extensive experience delivering results. Nexio Projects has supported 400+ clients across more than 1,000 projects in over 20 countries.
Service offering: The consultancy’s portfolio should match your company’s needs, offering detailed gap analyses, multi-year improvement roadmaps, support with implementation, post-certification impact planning, and training programmes for employees and leadership.
Geographical and sector expertise: Choose consultants who understand local and global markets, regulations, and industry-specific challenges. Nexio Projects operates worldwide with strong expertise in Europe and North America, and deep knowledge in key sectors such as shipping & logistics, manufacturing, chemicals, and consumer goods.
Transparency and collaboration: Sustainability is a continuous journey. The right partner prioritises open communication, customised strategies, and long-term impact building instead of a tick-box exercise.

5 leading ESG consultancies for mid-market companies

Here are five consultancies recognised for their expertise serving mid-market organisations:

Nexio Projects

Nexio Projects is an international sustainability consultancy based in Rotterdam, guiding organisations from compliance to purpose. Our diverse group of professionals partners with mid-market and larger organisations to tackle complex sustainability challenges, offering services from climate decarbonisation strategies to ESG ratings and reporting frameworks.

Recognised by Verdantix as one of the top 10 boutique ESG consultancies globally, we have upheld the highest standards of social and environmental performance as a Certified B Corporation since 2018. With over 400 successful partnerships worldwide, we empower clients to achieve their sustainability ambitions and make a meaningful impact. Our experience across industries and regions allows us to deliver tailored, practical solutions that drive tangible change for mid-market organisations.

Hear more from our clients about ESG collaborations.

Good.Lab

Based in the US but operating globally, Good.Lab offers strategic sustainability consulting with an emphasis on technology-enabled ESG solutions for mid-market companies. Their services include ESG strategy formulation, reporting, and supplier engagement.

South Pole

A global sustainability solutions provider specialising in carbon management, ESG risk assessment, and climate strategy tailored for mid-sized enterprises, particularly in manufacturing and logistics sectors.

H&Z Management Consulting

A European consultancy providing strategic ESG advisory and practical implementation support to mid-market firms, especially in industrial sectors like aerospace, automotive, and manufacturing. Their approach blends strategy with hands-on delivery to help companies turn ESG compliance into growth opportunities.

EcoAct

With roots in Canada and global reach, EcoAct specialises in carbon reduction strategies and sustainability advisory for mid-market businesses across diverse sectors. They focus on climate risk management, sustainable supply chains, and ESG reporting support.

What makes Nexio Projects unique?

Nexio Projects stands apart due to its blend of hands-on experience and a boutique consultancy spirit that values the uniqueness of each client. Rather than offering generic solutions, we develop bespoke strategies aligned with each company’s individual context and sustainability ambitions. Our strategic partnerships with industry leaders combined with recognition as a top sustainability consultancy enable us to integrate technical ESG expertise with creative problem-solving and collaborative support. This comprehensive and personalised approach empowers mid-market companies to navigate complex sustainability challenges confidently and effectively.

We help mid-market organisation through a wide range of solutions, such as:

EcoVadis: As a leading EcoVadis strategic partner, we guide you through the assessment process and help improve your score year after year.

B Corp: Our in-house B Leaders and sustainability experts support you throughout your B Corp certification journey.

ESG reporting: ESG reporting specialists and chartered accountants help you navigate reporting requirements and achieve compliance for multiple frameworks.

Sustainability strategy: Define, develop, and implement an integrated sustainability strategy with expert support.

Net zero & decarbonisation: Our climate experts help shape your emissions reduction strategy and set targets aligned with standards such as SBTi.

Climate risk & CDP reporting: Gain clarity on climate risks and opportunities to strengthen your net-zero strategy and simplify CSRD, TCFD, and CDP disclosures.

Product sustainability: Discover insights into the full life cycle impacts of your products and services with our product sustainability experts.

Outsourced sustainability management: We help develop and execute impactful sustainability strategies and initiatives through our outsourced service.

Take the next step in your ESG journey

Partnering with the right ESG consultancy can transform your sustainability efforts from a compliance obligation into a strategic advantage. Contact Nexio Projects today for a free consultation to discuss how to tailor an ESG strategy that supports your growth, compliance, and impact goals.

Contact us today for a free consultation call to discuss the ESG strategies tailored for your organisation.

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