Customer Requested Carbon Data? Here's What UK Businesses Must Provide
Customer Carbon Data Requests
A customer requested carbon data — here's exactly what to send
Most UK suppliers still answer these requests with a folder of old bills and an email. GreenKPO turns the same request into a structured, evidenced Scope 1 & 2 submission your customer can actually use — usually within one working week.
What is your customer actually asking for?
Carbon data requests can look intimidating, but most of them boil down to a handful of things. Your customer is almost always trying to complete their own Scope 3 reporting, a supplier sustainability scorecard, or a due diligence questionnaire ahead of a tender. They need your numbers to fill a gap in their own calculations — they are not testing you, and in most cases they are not expecting perfection.
Usually mandatory: total annual emissions in tCO2e, a Scope 1/Scope 2 split, the reporting period, and the organisational boundary. Usually optional but strengthens your response: Scope 3 estimates, intensity ratios, a methodology note, and third-party verification.
Immediate checklist: what to gather before you reply
Before drafting anything, pull together the following. Having this in hand first means you write the response once, rather than going back and forth.
- Reporting period — start and end date, usually matching your financial year
- Organisational boundary — which sites, subsidiaries or operations the figures cover
- Activity data — electricity and gas bills, fuel receipts, fleet mileage, travel records
- Emission factors — current UK Government conversion factors for the year in question
- Calculations — Scope 1 and Scope 2 totals, plus Scope 3 estimates if requested
- Supporting evidence — copies of the bills and invoices used, kept on file for audit
Step-by-step: putting together your response
- 1. Read the request carefully. Identify exactly which scopes, time period and format are being asked for before calculating anything.
- 2. Gather your activity data. Collect twelve months of energy bills, fuel receipts and mileage records covering your boundary.
- 3. Apply the correct emission factors. Convert each activity into tCO2e using UK Government factors for the relevant year.
- 4. Total your figures by scope. Sum Scope 1 and Scope 2 separately; label Scope 3 estimates clearly if included.
- 5. Check your numbers. Cross-reference against last year's figures and sense-check your intensity ratio.
- 6. Add a short methodology note. A few lines on boundary, factors and exclusions usually prevents follow-up questions.
- 7. Send it in the format they asked for. Complete their portal or form directly rather than attaching a separate document.
Common mistakes to avoid
- Mixing reporting periods — using bills from different financial years skews the total and is easy for a reviewer to spot.
- Presenting estimates as measured data — unlabelled estimates undermine trust if they're later queried.
- Confusing Scope 2 with Scope 3 — purchased electricity is Scope 2; goods, commuting and travel in vehicles you don't own are Scope 3.
- Losing the supporting evidence — a total with no bills behind it can't survive a follow-up query or supplier audit.
- Sending unsupported totals — a number with no boundary, period or methodology reads as unverifiable.
How GreenKPO removes the manual work
Most of the effort in answering a carbon data request goes into finding the right bills, applying the correct factors, and building a submission a customer won't send back with questions. GreenKPO pulls in your utility and fuel data, applies up-to-date UK emission factors, and generates a submission-ready breakdown by scope — with the underlying calculations and source records attached, so you can point to evidence if anyone asks. It doesn't replace your judgement on boundary or methodology decisions; it removes the spreadsheet work behind them, so a request like this takes hours rather than weeks.
Common questions
- Do I legally have to provide carbon data if a customer asks?
Not usually, unless your contract requires it. But refusing can put the relationship or contract at risk, since many large customers now treat supplier data as a condition of doing business. - What if I've never calculated my emissions before?
Say so, and give a realistic timeline. Most customers accept a first-time calculation, especially from smaller suppliers, as long as you communicate clearly rather than going quiet. - Is it okay to only provide Scope 1 and Scope 2?
Often, yes — many requests only require Scope 1 and 2 initially. Check the request wording; if Scope 3 isn't explicitly asked for, don't hold up your response trying to calculate it. - What format should I send the data in?
Match whatever the customer used to ask. Complete their form or portal fields directly; only send a separate report or letter if that's what they requested. - How accurate do my numbers need to be?
Reasonably accurate and clearly documented is usually enough. Label estimates as estimates and explain your methodology briefly. - What happens if my numbers are challenged later?
This is why keeping source bills, receipts and calculation records matters. If you can show how a figure was derived, most queries are resolved quickly.
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Prepare the carbon data your customer requested
Get your Scope 1 and 2 figures, methodology note and supporting evidence pulled together — without building a spreadsheet from scratch. Most clients have their first submission-ready pack within a working week.