If you need a carbon footprint for a board, customer, tender or reduction plan, the total is only part of the job. You also need to know what sits inside it, which data you can trust and where estimates have been used.
C Level has worked with business carbon since 2000. We calculate corporate Scope 1, Scope 2 and relevant Scope 3 emissions, undertake more involved value-chain and product footprint work, and leave you with the workings behind the answer.
For a straightforward company, we will not turn that into a sprawling consultancy project. If the footprint is complicated, particularly once Scope 3 gets involved, we will not tidy away the uncertainty to make the report look cleaner.
If you already have good operational data and mainly want an initial calculation, try our Business Carbon Footprint Calculator first.
What we check before we trust a carbon footprint
Suppose you send us electricity bills for two offices, mileage records, a flight report and a purchase ledger. There is plenty to calculate, but we would not start with emission factors.
First, we need to know whether those two offices are the whole reporting organisation. Are there leased sites or subsidiaries outside the pack? Does the purchase ledger cover the same reporting year? What will the finished footprint be used for?
Get the organisational boundary wrong and the calculation can be internally tidy while still answering the wrong question.
Then we look at the evidence. A meter reading in kWh is different from an annual spend figure. If you know you burned 8,000 litres of diesel, I would use the litres rather than estimate fuel use from the invoice value. If a large purchasing category is represented only by £80,000 of spend, that may be useful for screening, but I would not pretend it carries the same confidence as measured activity data.
This is where carbon footprint consultancy earns its place. The arithmetic is rarely the difficult part. The useful work is deciding which evidence deserves confidence, which gaps could materially change the result and where another week of data collection would barely move it.
Our carbon footprint consultancy services
Corporate carbon footprints
We calculate the greenhouse gas emissions associated with your organisation over an agreed reporting period, using the GHG Protocol Corporate Standard as the main corporate accounting framework.
The first decisions are practical: which entities, sites and activities sit inside the inventory, and what year are we measuring? We then calculate Scope 1 and Scope 2 emissions and establish how Scope 3 should be treated for the work you need.
For UK activities, we use the UK Government conversion factors for company reporting where appropriate. We record the factor set, source and methodology rather than leaving them buried in a black box.
If the footprint is intended for a customer request, procurement process, SECR reporting or another defined purpose, tell us at the outset. Our guide to SECR reporting requirements sets out which companies qualify, what has to be disclosed and what a calculator does not establish on its own. Retrofitting a reporting requirement after the calculation is finished is avoidable work.
Scope 3 consultancy
Scope 3 is where a carbon footprint can become expensive if nobody decides what matters.
The GHG Protocol Scope 3 Standard divides value-chain emissions into 15 upstream and downstream categories. We screen all 15 first. That does not mean spending the same amount of time on all 15.
A manufacturer buying large quantities of materials has a different problem from a professional services company dominated by travel and purchased services. We identify the categories that are relevant, look at which appear material and inspect what evidence exists. Supplier-specific figures may be available. You may have tonnes, kilometres or units. Sometimes spend is the only sensible starting point.
If a category is excluded from work being prepared to the Scope 3 Standard, the exclusion needs to be visible and justified. Quietly dropping a difficult category is not a data-quality strategy.
Nor is equal effort automatically good practice. Improving an immaterial category from a rough estimate to a beautifully researched estimate can consume staff time without changing a decision. If purchased goods dominate the footprint, that is where I would want the better evidence.
Product carbon footprints
A product carbon footprint needs its own boundary. Depending on the question, raw materials, manufacture, transport, use and end of life may all matter.
We undertake product footprint work through Bespoke Carbon where the necessary product and supply-chain information can be established. We agree what is being measured before the detailed calculation begins. Otherwise it is remarkably easy to spend time refining life-cycle stages that do not belong in the answer.
Carbon reporting and reduction planning
A footprint may need to support SECR, a PPN 006 Carbon Reduction Plan, customer reporting, internal targets or a wider reduction programme. The intended use affects the evidence and documentation you need.
Once the inventory is built, we look at what is actually driving it. If electricity is 4% of your total and business travel is 46%, changing the office lighting may be a worthwhile housekeeping measure, but it is not where I would start if the aim is to cut the footprint materially.
The figures should help you choose where to spend time and money.
How the consultancy works
We agree the purpose and boundary first, then ask for the data that is actually relevant to your business. That normally means a targeted request rather than a vast generic spreadsheet with every conceivable carbon category in it.
We review what comes back, raise the questions that could change the result and calculate from the strongest available evidence. Where a material category is weak, we say so. Where an estimate is good enough for the decision in front of you, we do not manufacture extra work simply to make the exercise look more sophisticated.
The final stage is a review of the footprint and its implications. You should know what the main sources are, where the uncertainty sits and what would be worth improving before the next reporting cycle.
What you get from C Level
The exact output depends on the brief. A corporate footprint can include:
- total emissions in tonnes of CO₂e;
- Scope 1, Scope 2 and relevant Scope 3 calculations;
- emissions broken down by significant source;
- the organisational and reporting boundary;
- data and emission-factor sources;
- significant assumptions, estimates and exclusions;
- carbon hotspots and reduction priorities;
- areas where better data would improve the next reporting cycle;
- the methodology and calculations needed to understand how the result was reached.
You should be able to pick up the work six months later and see why a figure is there. If your finance director asks why freight rose, or a customer asks what is included in Scope 3, somebody inside your business should be able to answer without coming back to us simply to decode the report.
I do not see much value in a polished carbon report that nobody inside the company can explain. Black-box accounting leaves you dependent on the consultant and makes year-on-year comparisons harder to interrogate.
There is another boundary we keep clear because C Level also works with carbon and nature projects. If your corporate footprint is 620 tonnes of CO₂e, funding 620 tonnes of carbon credits does not turn the inventory into zero. Your reported Scope 1, Scope 2 and Scope 3 emissions remain the emissions you calculated. Carbon credits for business are a separate decision.
Where weak carbon accounting tends to show up
The most serious problems are often easy to miss in a polished PDF.
The boundary is the first place we look. If a material subsidiary, leased operation or relevant Scope 3 category is outside the calculation, the total may be perfectly calculated and still be unsuitable for what you want to do with it. We make exclusions visible so you can see what the number actually covers.
False precision is another warning sign. Carbon accounting often combines meter readings, litres of fuel and recorded mileage with estimates and financial proxies. A result of 426.37 tonnes looks exact. The underlying evidence may not be. Another decimal place does not repair weak source data.
Missing data needs similar care. On 31 July 2026 the UK Government reissued the flat-file version of its 2026 conversion factors, to correct a number of values that had first been published as 0. Zero and unknown are not the same thing. If a material source is unquantified, we would rather show the gap than quietly convert it into no emissions.
A first footprint does not need every uncertainty eliminated. It does need the important uncertainties exposed.
Base Carbon or Bespoke Carbon?
The right amount of consultancy depends on where the uncertainty is. A simple company with good records does not need the same investigation as a group with several entities and a large value-chain footprint.
Base Carbon
Base Carbon is for a defined first corporate footprint: typically Scope 1, Scope 2 and straightforward relevant Scope 3 sources, with enough analysis to identify the main emissions and sensible next steps.
It suits relatively simple businesses whose main need is a credible baseline. Buying days of consultancy to chase tiny categories adds cost without improving the decision.
Bespoke Carbon
Bespoke Carbon is for businesses where the difficult part genuinely needs investigation: substantial Scope 3 emissions, several entities or sites, complex purchasing, supplier work, product footprints or more involved reporting requirements.
For Bespoke Carbon, we spend the time where the uncertainty actually is. If purchased goods dominate the footprint, that is where the work should go. If your operational footprint is already well evidenced, there is no prize for recalculating it at greater length.
Do you need a carbon footprint consultant at all?
Not always.
If your business is straightforward, your energy, fuel and travel records are in reasonable order and you mainly want an initial operational footprint, our business carbon footprint calculator may be enough.
Consultancy earns its place when the difficult questions are about organisational boundaries, Scope 3, weak data, product-level analysis or a report that somebody else will rely on.
If we think the calculator is enough for what you need, we will tell you. Paying a consultant to type clean data into boxes is an expensive way to use a consultant.
Carbon footprint consultancy since 2000
C Level was founded in 2000. Our carbon team includes Moris Otto, Lead Carbon Analyst, Briony Fitzsimmons, Senior Carbon Analyst, and founder Daren Howarth. C Level has been a Certified B Corporation™ since February 2017.
We work with organisations including Springer Nature, Zurich, Euronews and Numatic.
Springer Nature’s climate programme has included Scope 1, Scope 2 and business-flight Scope 3 emissions. Its wider relationship with C Level has also involved climate-project selection, where its internal working group included editors from its climate and sustainability journals.
Can your carbon footprint be independently verified?
Yes, if independent assurance is required. Producing the inventory and independently verifying it are different jobs.
Our role is to establish the boundary, methodology, evidence and calculations. The work should then be clear enough for an appropriately qualified third party to examine. We do not describe our own calculation as independent verification.
The corporate accounting standards are also changing. On 29 July 2026 the GHG Protocol and the International Organization for Standardization announced that they will combine their corporate carbon accounting standards into a single co-branded standard, with a public consultation planned for the second quarter of 2027. That makes version control more important, not less. We record the standard, factor set and methodology used so you can see what your inventory was built against if requirements change later.
Standards and primary sources
Our work draws on current primary guidance rather than supplier summaries. All sources checked 24 August 2026. The sources most relevant to this service are:
- GHG Protocol, Corporate Accounting and Reporting Standard, the main framework for corporate Scope 1 and Scope 2 accounting. Source.
- GHG Protocol, Corporate Value Chain (Scope 3) Standard, which sets out the 15 value-chain categories. Source.
- UK Government, greenhouse gas reporting conversion factors 2026, used for UK activity data. Source.
- UK Government, environmental reporting guidelines including SECR guidance. Source.
- UK Government, PPN 006 on Carbon Reduction Plans in major government procurement. Source.
- GHG Protocol and ISO, announcement of a single harmonised corporate standard, 29 July 2026. Source.
Frequently asked questions about carbon footprint consultancy
What does a carbon footprint consultant do?
A carbon footprint consultant defines what belongs in the inventory, reviews the underlying data, calculates the relevant Scope 1, Scope 2 and Scope 3 emissions and documents how the result was reached. The useful consultancy work begins where the boundary, data or intended use of the footprint needs judgement.
How much does carbon footprint consultancy cost?
A single-company baseline with good records is a different job from a multi-entity Scope 3 exercise with weak supplier data, so there is no useful one-price answer. Base Carbon keeps simpler work contained. Bespoke Carbon is scoped around the investigation required.
What information will you need from us?
For many companies the first pack includes energy bills or meter data, fuel records, mileage and travel. Scope 3 may bring in purchasing, freight, waste, employee, supplier and product information. You do not need to arrive with every answer. We would rather identify the material gaps than send you a generic spreadsheet and ask you to fill every cell.
Do you calculate Scope 3 emissions?
Yes. We screen the 15 Scope 3 categories first and then concentrate effort where the categories are relevant and material. Straightforward Scope 3 sources can sit within Base Carbon; substantial value-chain work belongs in Bespoke Carbon.
Can C Level calculate a product carbon footprint?
Yes, where the product boundary and necessary supply-chain data can be established.
Can you help with SECR and Carbon Reduction Plans?
Yes. Tell us what the footprint has to support before we start, so the calculation is built for the current requirement rather than retrofitted later. For central government procurement, see our guide to PPN 006 Carbon Reduction Plans.
How often should we calculate our business carbon footprint?
Usually once a year if you want to track change. Watch for changes in the reporting boundary, factor set or methodology between years, because a movement in the total can otherwise look like business progress when the accounting changed underneath it.
Talk to our carbon team
Tell us what you need the footprint for, what the business looks like and what data you already have. We can tell you whether the sensible next step is Base Carbon, Bespoke Carbon or the Business Carbon Footprint Calculator.