Compare Your Footprint — Carbon Intelligence Platform

Since September 2025, every UK business using Sage Accounting has had carbon reporting built into their existing software at no extra cost. Sage Earth, bundled free with all Sage Accounting and Sage for Accountants plans, uses AI to categorise bank transactions and estimate the carbon emissions associated with business spending.

This is a significant development. Millions of UK SMEs now have a route to carbon awareness without buying new software or hiring a consultant. For many businesses, Sage Earth will be their first encounter with the concept of a carbon footprint.

But there is an important distinction between a carbon estimate and carbon data — and understanding when you have outgrown the former is critical.

What Sage Earth does well

Sage Earth’s approach is elegant in its simplicity. It reads your bank transactions, categorises your spending using AI, and applies industry-average emissions factors to produce an estimate of your carbon footprint. You do not need to enter any additional data. If you use Sage Accounting, the carbon estimate appears automatically.

For a business that has never thought about carbon, this is genuinely valuable. It provides a directional sense of where your emissions come from — is it mostly energy, travel, purchased goods, or something else? It normalises the idea of carbon measurement within the accounting workflow. And it costs nothing beyond your existing Sage subscription.

Sage Earth also integrates with Xero and QuickBooks, extending this capability beyond the Sage ecosystem. Standalone SMB access starts at £9 per month.

If your goal is to answer the question “roughly how much carbon does my business produce, and what are the big categories?” — Sage Earth delivers.

Where spend-based estimation falls short

The challenge arises when someone asks you for more than a rough estimate. And increasingly, someone will.

When a customer sends a supply chain questionnaire. Large companies reporting under CSRD, UK SRS, or aligning with the GHG Protocol’s Scope 3 standard need emissions data from their suppliers broken down by category. They want to know your Scope 1 emissions (direct combustion), your Scope 2 emissions (purchased energy), and your material Scope 3 emissions — each as a separate, calculated figure with a documented methodology. A spend-based estimate cannot produce this breakdown because it does not collect the underlying activity data.

When accuracy matters more than convenience. Spend-based estimation applies industry-average emissions factors to your spending. This means a company that has invested heavily in energy efficiency and a company that has not will produce similar estimates if they spend similar amounts. The methodology cannot distinguish between a supplier buying green energy and one running on coal. For competitive positioning or genuine reduction planning, this is a fundamental limitation.

When you need audit-ready data. Spend-based estimates carry an inherent uncertainty that makes them difficult to defend in an audit context. If a consultant, auditor, or customer asks “how did you calculate this number?” the answer “our accounting software estimated it from our bank transactions” does not carry the same weight as “we collected our energy bills, fuel receipts, waste records, and freight data and applied GHG Protocol emission factors.”

When you are tracking progress year on year. If your carbon footprint goes down, you want to know whether it went down because you actually reduced emissions or because you spent less money that year. Spend-based methods cannot separate operational improvement from economic fluctuation. Activity-based measurement can.

When the GHG Protocol revision lands. The March 2026 Phase 1 Progress Update for the Scope 3 Standard revision proposes mandatory disaggregation of primary versus secondary data. Spend-based estimates will be classified as secondary data. Companies will have a structural incentive to obtain primary, activity-based data from suppliers. If your data is spend-based, you are on the wrong side of that incentive.

The two methodologies, compared

Spend-based estimation takes your financial transactions and multiplies them by emissions factors expressed in kgCO2e per pound spent. The data source is your bank account. The advantages are zero additional data collection, automatic calculation, and very low effort. The limitations are low accuracy, no Scope breakdown by activity, inability to reflect actual operational choices, and classification as secondary data under evolving standards.

Activity-based measurement collects your actual operational data — kilowatt-hours of electricity, litres of fuel, tonnes of waste, kilometres travelled — and applies specific emissions factors to each activity. The data source is your utility bills, fuel invoices, waste transfer notes, and transport records. The advantages are high accuracy, defensible methodology, ability to track real progress, GHG Protocol alignment, and classification as primary data. The main cost is that it requires you to gather and enter operational data.

When to stay with Sage Earth

Sage Earth is the right tool if:

You are a small business with no current customer or regulatory requirement to report carbon data.
You want a first directional view of where your emissions sit.
You have no plans to respond to detailed supply chain questionnaires or bid for government contracts requiring a Carbon Reduction Plan.

In this scenario, Sage Earth provides useful awareness at zero marginal cost. There is nothing wrong with starting here.

When to step up to activity-based measurement

You need a dedicated carbon measurement platform when any of the following apply:

A customer has asked — or is likely to ask — for your emissions data broken down by Scope or by GHG Protocol category.
You are bidding for UK central government contracts over £5 million per year and need a Carbon Reduction Plan under PPN 06/21.
You want to set reduction targets and track genuine operational progress year on year.
A consultant or auditor needs to verify your carbon data.
You supply into EU markets and expect VSME-aligned data requests under CSRD-driven supply chain reporting.
You want to benchmark your carbon performance against similar businesses in your sector.

CYF: built for the transition point

Compare Your Footprint (CYF) is designed for the moment a business outgrows spend-based estimation. CYF collects actual activity data — energy, fuel, waste, water, travel, freight, and supply chain inputs — and calculates emissions using GHG Protocol methodology with regularly updated, UK-specific emission factors.

The output is audit-ready, Scope-disaggregated, category-level carbon data. When a customer sends you a supply chain questionnaire asking for your Scope 3 Category 4 (upstream transportation) emissions, CYF gives you the number. When your consultant needs to verify your methodology, CYF documents the calculation chain from raw data to reported figure.

CYF also provides benchmark data, showing how your carbon performance compares to similar businesses. This is something no spend-based tool can offer, because benchmarking requires consistent, activity-based data to be meaningful.

The practical path forward

If you are already using Sage Earth, keep using it. The awareness it creates is valuable, and it costs you nothing.

But when the first detailed data request arrives — and it will — recognise it as the signal to step up. Invest an afternoon collecting your energy bills, fuel records, and waste data. Enter them into a tool built for activity-based measurement. Produce your first real carbon footprint.

The difference between “we have an estimate” and “we have measured data” is the difference between a supplier that large companies tolerate and one they trust. In a market where carbon data is becoming a procurement criterion, that trust has real commercial value.

Sage Earth is your first step. Activity-based measurement is what your customers are actually asking for.

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Sources: Sage Earth announcement (September 2025), AccountingWeb Sage Earth review, Sage Earth SMB page