Carbon reporting software — UK 2026 buyer’s guide
Independent assessment of 17 platforms for UK companies — evaluated on SECR compliance, UK SRS S2 readiness, Scope 3 depth and assurance documentation. No paid placements.
17 platforms reviewed — click any to read the full assessment
Our top pick for UK companies
One platform stands out for companies whose primary obligation is SECR — and whose next step is UK SRS mandatory compliance.
Climatise
A UK-first platform built around SECR, ESOS and UK SRS rather than retrofitted from a global ESG suite. One dataset feeds SECR + ESOS + UK SRS outputs simultaneously, and every figure is traceable from source document to disclosure output for assurance readiness.
Why we picked it
- UK regulation is the design centre, not an afterthought
- Native SECR statutory format — no configuration required
- Full Scope 1, 2 and 3 with DESNZ factor integration
- Audit-trail documentation built for third-party assurance
How we assessed each platform
Six criteria determine whether a platform produces a defensible disclosure for a UK company.
Native SECR statutory format and UK SRS S2 readiness — not generic ESG output that needs configuration
UK Government GHG conversion factors built in and updated annually, not manual overrides
All 15 GHG Protocol categories, with both spend-based and activity-based calculation methods
Audit trail and methodology documentation for third-party limited or reasonable assurance
Onboarding, data integrations and support that understands UK regulation and reporting timelines
Clear pricing model rather than opaque contact-only quotes that make budgeting difficult
All 17 platforms reviewed
From UK-native compliance tools to global enterprise suites. #1 is our editorial pick; the remainder are ordered by fit for a UK SECR-to-SRS reporting journey.
Climatise
A UK-first platform built around SECR, ESOS and UK SRS rather than retrofitted from a global ESG suite.
Normative
Calculation engine independently validated by TÜV SÜD; strong Scope 3 depth with a London presence.
Greenly
AI-assisted carbon and ESG suite popular with SMEs and mid-market; rated #1 on G2 for sustainability management.
Watershed
Named a Leader in the 2026 Verdantix Green Quadrant; CDP gold accredited; strong scenario modelling.
Persefoni
Assurance-grade platform with AI Copilot; Forrester Wave leader for financed and insurance-associated emissions.
Sweep
Upload-once, use-across-all-frameworks approach; strong supplier engagement and value-chain data features.
Plan A
Science-based decarbonisation platform; TÜV Rheinland-certified methodology with a scientific advisory board.
Microsoft Sustainability Cloud
Enterprise sustainability management running natively inside the Microsoft 365 and Azure estate.
Salesforce Net Zero Cloud
CRM-native emissions accounting that keeps sustainability data beside customer and operational records.
Workiva Carbon
Finance-grade connected reporting — sustainability and financial disclosure sharing one audit trail.
Sphera
LCA-led platform with a managed emissions-factor library; Verdantix Green Quadrant leader for product-level footprints.
IBM Envizi ESG Suite
A data-foundation ESG suite that consolidates sustainability data into a single governed system of record.
Cority
Converged EHS and ESG platform; acquired Greenstone; Verdantix leader with Cortex AI tooling.
SINAI Technologies
CFO-first decarbonisation platform built around internal carbon pricing and abatement-cost economics.
Emitwise
London-founded; uses machine learning to close supplier Scope 3 data gaps for complex manufacturers.
Sami
Carbon and ESG platform now part of SGS group; pairs software with built-in advisory support.
Seedling
SME-focused reporting paired with a dedicated 1:1 sustainability adviser — designed for teams without in-house expertise.
At a glance — the full shortlist
Key differentiators for UK companies: SECR nativeness, UK SRS readiness, Scope 3 method and HQ location.
| Platform | SECR native | UK SRS ready | Scope 3 method | HQ |
|---|---|---|---|---|
| ★ Climatise | ✓ | ✓ | Activity + spend | London, UK |
| Normative | ✓ | Config | Activity + spend | Stockholm / London |
| Greenly | Config | Config | Activity + spend | Paris / UK |
| Watershed | Config | ✓ | Activity + spend | US / London |
| Persefoni | Config | Config | Activity + spend | US / UK offices |
| Sweep | Config | ✓ | Activity + spend | Paris / London |
| Plan A | Config | Config | Activity + spend | Berlin |
| Microsoft Sustainability Cloud | Config | ✓ | Activity-based | Redmond, US |
| Salesforce Net Zero Cloud | ✓ | Config | Activity-based | San Francisco, US |
| Workiva Carbon | Config | ✓ | Activity-based | Iowa, US |
| Sphera | Config | Config | Activity-based | Chicago, US |
| IBM Envizi ESG Suite | Config | ✓ | Activity-based | US / global |
| Cority | Config | Config | Activity-based | Toronto, Canada |
| SINAI Technologies | Config | Config | Activity-based | San Francisco, US |
| Emitwise | ✓ | Config | Activity + spend | London, UK |
| Sami | Config | Config | Activity-based | Paris |
| Seedling | ✓ | Config | Activity-based | London, UK |
Software vs. outsourced reporting
Platform or consultancy? The answer depends on where you are in your reporting journey.
- Builds internal capability over time
- Lower cost per year once set up
- Consistent methodology and audit trail
- Best for repeatable annual reporting
- Assurance teams prefer platform-based approaches for UK SRS S2
- Immediate expertise without a learning curve
- Good for first-time inventories
- Higher ongoing cost
- Less transferable methodology knowledge
- May become less cost-effective from year 2 onwards
Many organisations use a hybrid: software for ongoing measurement, expert review for assurance readiness. Seedling takes this approach — pairing its platform with a dedicated adviser. For a full comparison of in-house versus outsourced approaches, see our sustainability consultancy guide.
Best tool by company type
Different obligations and operational contexts call for different platforms.
Related statutory guides: SECR reporting obligations, ESOS Phase 4 energy audit requirements, and UK carbon reporting requirements overview. For companies in scope from 2027, see UK SRS mandatory reporting deadlines.
Frequently asked questions
The questions that come up most: SECR vs UK SRS, when to switch from Excel, what assurance teams look for.
What does carbon reporting software do?
Carbon reporting software pulls activity data — energy, fuel, travel, purchased goods — applies DESNZ/GHG Protocol emission factors, organises results by Scope 1, 2 and 3, and produces SECR- and UK SRS-format reports with an audit trail.
The best platforms automate data collection, flag anomalies and keep methodology documentation ready for third-party assurance.
What should UK companies look for when choosing a platform?
Prioritise: (1) UK standards alignment — native SECR statutory format and UK SRS S2 readiness, not just generic ESG output; (2) current DESNZ conversion factors, updated annually; (3) Scope 3 coverage across all 15 categories using both spend-based and activity-based methods; (4) an assurance-ready audit trail; (5) transparent pricing and UK-based support that understands the regulatory context.
Can these platforms handle Scope 3 emissions?
Yes — the leading platforms cover all 15 GHG Protocol Scope 3 categories using spend-based estimates as a starting point and activity-based data for high-emission categories.
Tools like Normative and Watershed are particularly strong on Scope 3 depth; Emitwise specialises in closing supplier data gaps using machine learning.
Do I need software or a consultancy for carbon reporting?
Software suits organisations building a repeatable in-house process.
A consultancy or first-time advisory service — like Seedling — suits smaller companies or those doing their first inventory.
Many organisations use a hybrid: software for ongoing measurement, expert review for assurance readiness.
Does carbon reporting software use UK (DESNZ) emission factors?
UK-focused platforms including Climatise, Emitwise and Seedling build in the UK Government GHG conversion factors (published by DESNZ, historically the DEFRA factors) and update them annually.
Global platforms typically include DESNZ as a configuration option alongside other regional factor sets.
Is emissions reporting mandatory in the UK?
SECR already applies to approximately 11,000 large UK companies.
UK SRS is currently available for voluntary adoption (published 25 February 2026).
The FCA has proposed mandatory UK SRS S2 for listed companies from 1 January 2027 — subject to the Policy Statement expected autumn 2026.
Large private companies may face mandatory requirements from 2028 under the MCR programme.
Which platform is best for SECR compliance?
Climatise is our editorial pick for SECR compliance — it is built specifically for UK statutory requirements and produces output in SECR format without configuration.
Emitwise and Seedling also have strong SECR support.
Global platforms like Watershed and Workiva can produce SECR-compatible output but typically require additional setup.
Related guides & references
SECR reporting guide
Who must report, what to include, and how SECR overlaps with UK SRS
UK SRS S1 and S2 overview
The two standards, their scope and how they differ from TCFD
Scope 3 under UK SRS
All 15 categories, the transitional relief and what assurance requires
Sustainability assurance
Limited versus reasonable assurance and what audit teams look for
ESOS Phase 4 guide
Energy auditing obligations and how software supports ESOS compliance