The sustainability advisory opportunity that most accounting and consulting firms are leaving on the table

Advisory and consulting now account for over a quarter of UK accounting firm revenues, according to the Accountancy Age Top 50+50 Rankings 2025. The firms pulling ahead are, almost without exception, the ones that have moved earliest and most decisively into high-value, recurring advisory services. Sustainability reporting is the next — and arguably the most substantial — of those services. Most firms haven't yet moved. That gap is the opportunity.

This article sets out the business case honestly: the real challenges of building a sustainability practice, the scale of the market need among SME clients, the commercial model that makes it work, and the platform that makes it operationally viable at scale without adding headcount.

Why the demand is structural, not cyclical

The pressure on businesses to measure and report their greenhouse gas emissions is not a trend that will pass. It is the product of overlapping regulatory frameworks that are progressively extending further down the supply chain — and the timeline is now.

In the UK, the Streamlined Energy and Carbon Reporting (SECR) framework already requires large UK companies and LLPs to disclose their energy use and Scope 1 and 2 emissions annually. The UK Sustainability Reporting Standards (UK SRS), published in February 2026 and based on the ISSB's global baseline standards, are expected to form the foundation of mandatory reporting requirements for a wider range of entities as the FCA's consultation progresses through 2026. Critically, those large in-scope organisations must report their Scope 3 emissions — which means they need data from their suppliers. That data requirement flows directly down the supply chain to the SMEs your clients are.

The pattern in public procurement is equally clear. The Procurement Act 2023, now in force, has made sustainability a core criterion in public sector contracting. PPN 06/21 requires Carbon Reduction Plans for contracts over £5 million. Suppliers that cannot demonstrate credible emissions measurement and reduction plans risk exclusion — and under the new rules, their names are published in award notices where ESG compliance has been a determining factor.

The scale of the unmet need:

Sources: Ltt Group market data; Sustainability Suite SME Regulations 2026 report

Those numbers represent a large, identifiable client base — most of whom already have a trusted relationship with an accountant or business advisor — facing a growing compliance risk they do not know how to address. The advisory firm that helps them address it first creates a durable, recurring engagement. The one that waits will find a competitor already in place.

The real barriers to building a sustainability practice

The business case for sustainability advisory is clear to most senior partners. The barriers to acting on it are equally clear — and more firms have been stopped by those barriers than by any lack of commercial appetite. It is worth naming them honestly.

The talent problem

Sustainability reporting requires a specific and relatively scarce combination of skills: an understanding of the GHG Protocol Corporate Standard, familiarity with emissions factor libraries and their update cycles, the ability to design and manage data collection processes across multiple emission sources, and working knowledge of the disclosure frameworks — CDP, SECR, CSRD, TCFD, SBTi — that clients may need to satisfy. This is not a skillset that exists in a typical accounting team, and it is not easily acquired through a short training programme.

Hiring a qualified sustainability consultant is one route, but the numbers are sobering. Average UK sustainability consultant salaries range from £37,000 to £55,000 at the senior end, rising to £60,000 or more for principal-level specialists — before employer on-costs of approximately 30%. A dedicated hire to service a nascent sustainability practice carries significant fixed cost risk before the revenue base is established. And there is the further question of availability: qualified carbon accountants and sustainability reporting specialists are in short supply relative to demand, and that supply constraint is not resolving quickly.

The training gap

The alternative — training existing staff — is more accessible than it was five years ago. The ICAEW and Chartered Accountants Ireland have both invested in ESG skillset development for members. But training to a standard that enables a practitioner to confidently scope a client's GHG inventory, select the appropriate calculation methods, manage data collection, and produce a disclosure-ready output takes time. It is not a one-day course. And the knowledge depreciates quickly in a field where emissions factor libraries update annually, reporting framework requirements evolve, and client needs vary significantly by sector and size.

The data collection problem

Even where the expertise exists, the operational burden of actually running a carbon accounting engagement is considerable. A typical SME carbon footprint requires gathering data from multiple sources — utility bills, fuel receipts, fleet records, purchase ledgers, logistics data, travel expenses — often held in different systems, in different formats, with gaps and inconsistencies that require follow-up. In the absence of a structured platform, this process is managed through spreadsheets, email chains and shared drives. It is time-consuming, error-prone, and almost impossible to replicate efficiently across multiple clients.

The practitioner who has spent two days chasing data for one client, then three days mapping it to emissions categories, then another day producing a report, understands intuitively why this model does not scale. At a fully-loaded cost of £500–£700 per day for a qualified consultant, the economics of a manually intensive carbon accounting service quickly become difficult for clients in the SME bracket — and difficult for the firm to deliver profitably.

The free tools trap

Free carbon calculators exist, and some firms have experimented with them. The limitation is not their cost — it is their scope. Most free tools are designed for basic Scope 1 and 2 estimation, with limited or no Scope 3 capability, no audit trail, no multi-client management, no framework-aligned reporting outputs, and no version-controlled emissions factor libraries. They are appropriate for a business doing a rough first estimate. They are not appropriate for producing a disclosure that will be reviewed by a corporate customer's procurement team, submitted to a public sector tender, or verified by a third party. Firms that have built client expectations on free-tool outputs and then needed to migrate to something more rigorous have found that transition more difficult than starting properly in the first place.

The commercial model: why sustainability advisory generates better economics than compliance

The commercial logic of sustainability advisory is structurally different from traditional compliance services — and more attractive on most dimensions that matter to an ambitious firm.

Compliance work — tax returns, annual accounts, statutory filings — is well understood, highly commoditised in many market segments, and subject to increasing fee pressure as automation reduces the labour content. Advisory work commands higher margins, stronger client relationships and better retention. According to Accountancy Age's Top 50+50 2025 Rankings, advisory and consulting now account for over a quarter of total fee income among the UK's leading firms, and the firms achieving the best revenue-per-partner ratios are consistently those with the strongest advisory service lines.

Sustainability advisory has an additional structural advantage: it is inherently recurring. A carbon footprint is not a one-off project. It needs to be updated annually as emissions factors change, as the business changes, and as the client's customers and regulators expect year-on-year comparison and evidence of progress. A client that engages an advisory firm for sustainability support in Year 1 has, in most cases, created a multi-year engagement. The ongoing measurement, reporting, supply chain engagement and reduction planning that follows an initial baseline creates a natural cadence of recurring work that does not have the same renewal risk as a compliance retainer.

Research from Sustainability Suite indicates that nearly half of UK mid-tier accounting firms are planning to launch ESG-related services within three years — up from just 10% in 2024. The window for early-mover advantage is measurable, and it is narrowing.

The firms that move now build client relationships, develop team capability and establish market positioning before the market becomes crowded. The firms that wait will find themselves competing on price in a service category that, by then, will have been standardised by those who moved earlier.

Why your SME clients are at risk right now — and what that means for you

The most immediate and commercially urgent issue for many of your clients is not regulatory compliance — it is supply chain qualification. Large corporations and public sector bodies are increasingly requiring their suppliers to provide verified emissions data, credible Carbon Reduction Plans and evidence of active decarbonisation programmes. As Small Business UK has reported, SMEs that can provide credible, consistent data are being seen as lower-risk partners, which is increasingly unlocking preferential terms, longer contracts and reduced insurance premiums. Those that cannot are being disqualified.

This creates a concrete, time-sensitive risk for your clients that you are well positioned to help them address. The accountant or advisor who identifies this risk, quantifies it in terms the client understands — lost contracts, procurement exclusion, financing disadvantage — and then provides a practical route to addressing it is delivering genuine, measurable value. That is exactly the kind of advisory engagement that deepens client relationships and justifies the kind of fee positioning that compliance work rarely can.

The data requests will become more frequent and more detailed over time. Larger organisations will request specific climate-related information from SMEs in their supply chain — activity data such as energy use, transport distances and waste volumes; progress against climate-related targets; and evidence of supplier engagement on emissions reduction. Clients who are unprepared when these requests arrive will be scrambling. Clients who have already built the data infrastructure and reporting capability will not.

How Vizibli makes it operationally viable

The barriers described above — talent scarcity, training investment, data collection burden, spreadsheet limitations — are real. They are also solvable, if the right platform is doing the systematic, repeatable work that should not require a senior sustainability specialist to perform manually for each client.

Vizibli is built specifically for accountants, consultants and advisory firms that want to deliver high-quality sustainability reporting to their SME clients at scale. The platform connects directly to a client's existing operational data — purchase ledgers, accounting exports, utility records, fleet management data — and maps it to the GHG Protocol framework automatically, applying the correct emissions factors from authoritative, version-controlled sources (DESNZ, Defra, Open CEDA, GLEC v3.2) across Scope 1, 2 and 3. The data collection process that typically takes weeks in a spreadsheet-based workflow takes hours in Vizibli.

The platform manages the entire workflow — from data ingestion and taxonomy mapping, through calculation and audit trail generation, to the production of framework-aligned reporting outputs for CDP, SECR, CSRD/ESRS E1, TCFD, GRI 305 and SBTi. Every calculation line is auditable. Emissions factors are updated automatically in line with annual publication cycles. The practitioner's time is redirected to the work that genuinely requires expert judgement: reviewing boundary decisions, advising on reduction priorities, engaging the client's supply chain, and communicating results to stakeholders.

The multi-client architecture is designed specifically for advisory firms. Rather than managing each client's carbon data in a separate spreadsheet or shared folder, practitioners manage their entire portfolio from a single dashboard. Onboarding a new client, running a year-end update for an existing one, or preparing a disclosure report for a corporate customer request are all handled within the same platform, with the same data quality standards applied consistently across every engagement.

The commercial model this enables is straightforward. Firms charge clients a monthly or annual retainer for ongoing sustainability measurement, reporting and advisory support. Vizibli's productivity improvement means that a single practitioner can manage a substantially larger client portfolio than would be possible in a manual workflow — which means the service is both affordable for SME clients and profitable for the firm. That combination, affordable delivery for clients and good margins for the firm, is what makes a new service line sustainable beyond the first few engagements.

What early-mover advantage looks like in practice

The firms that are moving into sustainability advisory now are doing so with a clear strategic rationale. They are identifying the clients in their existing portfolio that face the most immediate supply chain qualification risk — typically those in manufacturing, construction, healthcare, pharma and logistics, where corporate and public sector customers are already making emissions data a procurement requirement. They are proactively raising the issue with those clients, framing it as a commercial risk with a practical solution, rather than waiting for the client to bring it to them.

They are building the capability to deliver the service before the market fully understands what it needs — which means they are setting the standard rather than competing on price. And they are building recurring revenue streams from clients who, once engaged on sustainability, have an ongoing need for measurement, reporting, target-setting, supply chain engagement and reduction planning that creates a multi-year advisory relationship.

The window for that positioning is open. It will not stay open indefinitely. As Wonderful's 2025 analysis of the UK accounting profession observes, the firms embracing advisory evolution are gaining stronger client relationships, enhanced margins, and increased market share. Those that remain compliance-focused face a different trajectory.

The conversation worth having

If you are a partner or director at an accounting firm, management consultancy or advisory practice, the question is not whether your clients need sustainability support — they do, and the need is growing. The question is whether they will get that support from you, or from someone else.

Vizibli is designed to make that a straightforward decision. The platform removes the operational barriers that have prevented most firms from scaling sustainability advisory: the data collection burden, the spreadsheet limitations, the consistency challenges, the admin overhead. What remains is the advisory work — the commercial conversations, the risk framing, the client relationships — which is what ambitious firms and their people are built to do.