Carbon Accounting for Financial Services Companies in the UK

Financial services firms in the UK face a unique carbon accounting challenge. Unlike manufacturers or retailers, banks, insurers, and asset managers generate most of their emissions indirectly - through the companies they finance and the investments they hold. Understanding how to measure, report, and reduce these emissions is now a regulatory requirement under the Streamlined Energy and Carbon Reporting (SECR) framework.

This guide explains the emission sources that matter most for UK financial services, the regulatory landscape, and how leading firms are transitioning to climate-aligned portfolios.

Financial Services Emissions Overview - Why Scope 3 Dominates

For banks, insurers, and asset managers, Scope 3 Category 15 (financed emissions) typically accounts for 90-99% of total carbon footprint. This reflects the scale of capital deployed through lending, underwriting, and investment activities.

The Composition of Financial Services Emissions

Scope 1 and Scope 2 emissions come from direct operations: office energy, employee commuting, and business travel. These are material but represent a small fraction of total footprint.

Scope 3 emissions are where the impact lies. Financed emissions - the greenhouse gases emitted by companies in your lending and investment portfolio - dwarf operational emissions. A bank with $1 billion in corporate lending might have financed emissions thousands of times larger than its own carbon footprint.

Why This Matters for Compliance

UK financial services regulators, including the PRA and FCA, now expect firms to understand and disclose financed emissions. The transition to net-zero is being embedded into prudential supervision and market conduct frameworks. Carbon accounting in the UK has evolved from a voluntary ESG exercise to a compliance obligation.

Key Emission Sources for UK Financial Services Firms

Operational Emissions (Scope 1 and 2)

Office energy consumption is the largest operational source. UK financial services firms operate extensive real estate portfolios - headquarters, regional offices, and data centres consume electricity and heat.

Business travel is the second driver. Global asset managers, banks with international operations, and insurance brokers generate significant Scope 2 emissions from flights, rail, and vehicle rentals.

Employee commuting contributes incrementally but is harder to measure and control.

Financed Emissions (Scope 3 Category 15)

Financed emissions capture the carbon intensity of your lending and investment portfolios. For a bank, this includes:

• Corporate loan book carbon intensity
• Project finance emissions (energy, infrastructure, transport)
• Commercial real estate lending emissions
• Investment portfolio carbon intensity (for asset managers and insurers)

These emissions are typically reported as tonnes CO2e per £1m of capital deployed, making it easier to compare across different portfolio sizes.

SECR Requirements for Large UK Financial Services Firms

SECR applies to UK-listed companies and large private companies meeting two of three criteria: 250+ employees, £36m+ turnover, or £18m+ balance sheet total. Most major banks, building societies, insurers, and large asset managers fall within scope.

What Must Be Reported?

Qualifying firms must disclose annual energy consumption, greenhouse gas emissions (Scope 1 and 2), and intensity metrics. From 2026 onwards, large financial services firms face heightened expectations to include Scope 3 financed emissions in their carbon accounting.

Transition Timeline for Financial Services

The SECR framework requires disclosure in Directors' Reports from the financial year 2022-23 onwards (reported in 2023). Large financial institutions now have three full reporting cycles of historical data, enabling trend analysis and target-setting.

Many UK financial services firms voluntarily include Scope 3 financed emissions, recognizing that regulators will make this mandatory within the next 2-3 years.

PCAF Standard for Financed Emissions - The Methodology Leading Firms Use

The Partnership for Carbon Accounting Financials (PCAF) has become the global standard for measuring financed emissions in the UK and beyond. PCAF provides a standardized methodology for calculating carbon intensity across lending and investment portfolios.

How UK Banks Apply PCAF

Most large UK banks now use PCAF to measure portfolio carbon intensity. The methodology assigns emissions to financed activities based on:

• Company-reported emissions data (highest quality)
• Estimated emissions using sector averages and financial metrics
• Proxy data where direct measurement is unavailable

Portfolio carbon intensity is typically expressed as tonnes CO2e per £1m of capital. A bank might report that its commercial real estate loan book has a carbon intensity of 120 tCO2e per £1m, compared to an industry benchmark of 95 tCO2e per £1m.

How to calculate Scope 3 emissions explains the methodological foundation that PCAF builds on.

Transition Finance and Green Lending - Accounting for Climate-Aligned Portfolios

Leading UK financial services firms are now segmenting their portfolios by climate alignment. This distinction is important for carbon accounting and stakeholder disclosure.

Defining Green and Transition Assets

Green lending funds companies already operating at low carbon intensity: renewables, energy efficiency, sustainable transport. These are straightforward to measure using PCAF.

Transition lending supports high-emitting sectors (fossil fuels, steel, cement) in their decarbonization pathways. Accounting for transition assets requires credible climate commitments from borrowers and clear milestones for emissions reduction.

UK banks are developing transition finance frameworks to distinguish between aligned and misaligned portfolios. This allows more granular carbon accounting and supports the narrative that banking is actively financing decarbonization.

What emissions must UK banks report under SECR?

Scope 1 (direct emissions from owned operations) and Scope 2 (purchased energy) are mandatory. Scope 3 financed emissions are not yet required but are increasingly expected by regulators and investors. By 2027, expect financed emissions disclosure to become a compliance obligation for large institutions.

What are financed emissions and why do they matter?

Financed emissions represent the greenhouse gases emitted by companies you lend to or invest in. For a bank, financed emissions dwarf operational emissions. They matter because they reflect your firm's climate impact and inform regulatory capital requirements under emerging climate prudential frameworks.

How do UK financial services firms calculate Scope 3 emissions?

Most use the PCAF standard, which assigns portfolio emissions based on borrower-reported data, estimated emissions using financial metrics, or sector proxies. Carbon intensity is typically expressed as tonnes CO2e per £1m of capital deployed. Tools like Greenio automate this process at scale.

Does SECR apply to insurance companies?

Yes. Insurance companies meeting SECR thresholds (250+ employees, £36m+ turnover) must report energy and carbon data. Insurance firms should measure both operational emissions and financed emissions from their investment portfolios, which can be substantial for large insurers with £100bn+ in assets under management.

Conclusion

Carbon accounting for UK financial services firms is no longer optional. SECR compliance is mandatory for large institutions, and financed emissions disclosure is moving from voluntary to regulatory requirement.

By implementing PCAF-aligned methodologies, segmenting portfolios by climate alignment, and automating data collection, your firm can meet current requirements and prepare for tighter standards in 2027 and beyond. The transition to net-zero requires credible carbon accounting at every stage of the value chain.