Horizon ESG is an audit-ready sustainability reporting platform. It brings carbon accounting, multi-framework compliance, target management and AI automation together in one system, with a timestamped audit trail behind every number you disclose.
It is built for the finance, sustainability and risk teams who have to produce the numbers and then stand behind them, in organisations from single-entity mid-market companies through to multi-subsidiary groups.
WHY TEAMS CHOOSE IT
Sustainability information is now assured. Under CSRD it is subject to limited assurance from an independent provider, ISSA 5000 applies from 15 December 2026, and the ISSB-aligned regimes are moving the same way. That changes what a reporting platform has to do, because producing a well-formatted report is no longer the finish line. The platform has to be able to defend every figure in it.
Assurance providers working to ISAE 3000 (Revised) and ISAE 3410 test the process that produced your report: where the data came from, who entered it, what changed and why, which methodology was applied, and who approved the result. When that evidence lives in email threads and spreadsheet tabs, the engagement turns into an expensive document-retrieval exercise, and findings land at the point in the calendar where they are hardest to fix.
Horizon ESG is designed around that engagement. Every figure traces back through its calculation to the underlying activity data and the document it came from, whether that is an invoice, a meter reading or a supplier submission. Every entry, edit and deletion is timestamped and attributed to a named user, with the prior value retained. Emission factors are recorded with their dataset, reporting year and the basis on which they were selected. Preparation and approval are separated in the system rather than agreed over email, restatements are controlled and recorded, and reporting boundaries are documented so they reconcile to your financial consolidation.
FOUR MODULES, ONE CONNECTED WORKFLOW
Carbon Calculator. Scope 1, 2 and 3 emissions calculated on GHG Protocol methodology across your full operational boundary. Every assumption is documented and every data point is traceable. Emission factor selection is guided and validated, and multi-year trends are tracked as you go.
Compliance Reporting. Disclosures mapped across CSRD and ESRS, UK SRS, SECR, TCFD, ISSB and GRI, with pre-built data collection workflows for whichever regime applies to you. Automated completeness checks surface gaps before you submit rather than after, and outputs are formatted for stakeholders and for your assurance provider.
AI Automation. Data ingestion, cleansing and estimation are handled for you, with continuous data quality checks running in the background. Nova, the built-in ESG assistant, onboards your team, answers questions about your own data, matches emission factors and drafts narrative. Every Nova output is sourced, labelled and written into the same audit trail as manual entry, so an assurance provider can see exactly how a figure was reached and what part of it was machine-assisted.
Targets and Projects. Baselines established, science-aligned reduction goals set, and each initiative connected to a measurable outcome with a named owner, a deadline and live progress tracking. Decarbonisation trajectories can be mapped and reduction scenarios tested against live data.
FRAMEWORK COVERAGE
CSRD and ESRS, including double materiality. ISSB under IFRS S1 and S2. UK SRS S1 and S2, expected to apply to listed companies for financial years beginning 1 January 2027. SECR, with Companies House-ready outputs. TCFD across the four pillars of governance, strategy, risk management, and metrics and targets. GRI. GHG Protocol for Scopes 1, 2 and 3, including value chain emissions. One dataset serves all of them, so a figure entered once flows to every disclosure that needs it, with no duplicate entry and no reconciliation between framework workbooks.
The platform is equally useful outside mandatory scope. The Omnibus I Directive came into force on 18 March 2026 and raised CSRD thresholds to 1,000 employees and 450 million euro turnover, both tests met together, cutting EU scope from roughly 50,000 companies to around 5,000. That moved the pressure rather than removing it. Customers, banks and insurers who remain in scope pass their data requirements down the supply chain, and the same dataset that answers a CSRD disclosure answers a customer questionnaire or a lender request.
IMPLEMENTATION AND SCALE
Most organisations are live within two to four weeks. Setup is guided: define your organisational hierarchy, set reporting boundaries, import historical data from spreadsheets or an existing system with support from the implementation team, and the foundation is in place. There is no lengthy implementation programme and no requirement to bring in outside consultants to operate it.
The platform scales from a single entity to complex multi-subsidiary groups, with multi-site data collection, group consolidation and entity-level permissions. Your assurance provider or internal audit team can be given access directly, so evidence is reviewed in place rather than exported and emailed.
SECURITY AND DATA RESIDENCY
UK and EU data residency, with role-based permissions and an immutable, attributable change history across the platform.
BEST FIT
Organisations that report under more than one framework and are tired of reconciling between them. Teams heading into their first assurance engagement, or coming out of one with findings they do not want to repeat. Finance-led sustainability functions that expect the same standards of traceability, review and approval they already apply to financial reporting. Suppliers to large in-scope corporates who need to answer data requests quickly and consistently. Groups moving off spreadsheets who need their history to come with them.
Who Is the Company Behind Horizon ESG?
