Carbon Disclosure Project Questionnaire: A UK SME Guide

Every year, thousands of UK small and mid-sized suppliers get an email they were not expecting: "As part of our supply-chain climate programme, please complete our CDP questionnaire by [date]." Inside is a link to a 40-to-80 question assessment covering emissions, energy, climate risk, water, and targets.

Three days later the deadline panic starts.

This guide explains what the CDP questionnaire is, who actually has to respond, what it asks for, and how UK SMEs can answer it without burning a week. It is not a commercial pitch and it is not a CDP advisory product — just a direct walkthrough of what to expect and how to stay in control of your answers across years.

What CDP is (in one paragraph)

CDP (originally the Carbon Disclosure Project) is an international non-profit that runs the world's largest corporate environmental disclosure system. Companies and cities voluntarily disclose data through CDP's standard questionnaires on climate change, water security, and forests. Large buyers — from Microsoft and Unilever to national governments — use CDP's platform to score their suppliers' disclosures and drive supply-chain emissions down.

For a UK SME supplier, CDP usually shows up in one of two ways:

A large customer asks you to respond to their CDP Supply Chain programme as a condition of staying on their approved supplier list.
You self-declare a CDP disclosure — often because it is part of a certification, tender response, or investor relationship.

Either way, the questionnaire is the thing that lands on your desk.

Which CDP questionnaire is this?

CDP runs several standard questionnaires. The three you are most likely to meet as a UK SME:

Questionnaire	What it covers	Typical length
CDP Climate Change	Scope 1, 2, and 3 emissions, energy use, climate risks and opportunities, targets, governance, verification	40-80 questions
CDP Supply Chain (Climate)	Subset of the Climate Change questionnaire, plus supplier-specific questions (allocated emissions to your customer, engagement activities)	30-60 questions
CDP Water Security	Water withdrawal, discharge, risks, targets — only if your customer is tracking water-stressed supply chains	30-50 questions

The Supply Chain version is the one most UK SMEs receive. It is an abbreviated version of the main Climate Change questionnaire with a few extra "how much of your emissions are attributable to sales to us?" questions built on top. See CDP's Supply Chain programme page for current participants.

Do UK SMEs have to answer CDP?

Short answer: CDP itself is voluntary. But your customer's purchase order usually is not.

CDP is not a UK statutory requirement. There is no Companies Act clause, no HMRC filing deadline, no penalty letter. The regulatory regimes UK businesses must comply with are different — see our guides on SECR reporting and ESOS Phase 3 for those.

What CDP creates instead is commercial pressure. If your biggest customer has joined CDP's Supply Chain programme and requested your disclosure, ignoring it tends to mean:

Losing preferred-supplier status at contract renewal
Being deprioritised in tender scoring for new work
Having your customer's sustainability team chase your account manager weekly

For most UK SMEs in regulated supply chains, the honest position is: technically voluntary, practically mandatory.

What the Supply Chain questionnaire actually asks

The CDP Supply Chain (Climate) questionnaire maps to roughly eight areas. The exact wording changes year to year — CDP revises the questionnaire every January — but the shape is stable.

1. Governance

Who on your board or senior team oversees climate-related issues? How often do they review climate strategy? Is climate tied to any incentive scheme?

For an SME, the honest answer is usually: "Managing Director and Operations Director review emissions data quarterly. No formal incentive scheme linked to climate yet." That is an acceptable answer — CDP scoring recognises SME governance looks different from FTSE-100 governance.

2. Risks and opportunities

Identify climate-related risks and opportunities that could substantively affect your business, split into:

Physical risks (e.g., flooding at your main site, supply-chain disruption from extreme weather)
Transition risks (e.g., carbon pricing, customer preference shifts, loss of fossil-fuel contracts)
Opportunities (e.g., new low-carbon products, improved operational efficiency)

This is the section that catches most SMEs off-guard — it expects specific, locational answers, not boilerplate. "Our Sheffield manufacturing site has been flagged by the Environment Agency as at low-to-medium flood risk" is a stronger answer than "Flooding could affect our operations."

3. Business strategy

How is climate factored into your business planning? Do you use scenario analysis? Do you have a transition plan?

For SMEs this is often framed as: "Climate targets are integrated into our annual operational plan. We have not yet conducted formal scenario analysis aligned with IEA or IPCC pathways." Again, honesty scores better than overclaiming.

4. Targets and performance

Do you have an emissions reduction target? What is the base year, target year, scope, and percentage reduction?

CDP strongly prefers targets aligned with the Science Based Targets initiative (SBTi), but an internal, well-defined target scores points even without SBTi validation.

5. Emissions methodology

What standard did you use to calculate your emissions? (GHG Protocol is the default — see the Corporate Standard.) What boundary did you apply? Did you use operational or financial control? Did external verification happen?

For an SME without a full sustainability team, "GHG Protocol Corporate Standard, operational control boundary, DEFRA conversion factors, internal calculation (not externally verified)" is an acceptable and defensible position.

6. Scope 1, 2, and 3 emissions

The numeric heart of the questionnaire. Report your emissions in tonnes of CO₂ equivalent (tCO₂e) for:

Scope 1: Direct emissions from fuel combustion you control (gas boilers, company vehicles, refrigerant leaks)
Scope 2: Indirect emissions from purchased electricity, heat, or steam
Scope 3: Value-chain emissions (commuting, business travel, purchased goods, waste, customer use of products)

CDP accepts both market-based and location-based Scope 2 methods. For UK SMEs, the UK government conversion factors (published annually, most recently the 2025 set) are the standard source. Our Scope 1 and 2 emissions guide walks through how to calculate each.

7. Energy

Total energy consumption, split by fuel type, and the percentage from renewable sources. If you buy green-tariff electricity, you will need to distinguish between REGO-backed tariffs (stronger) and generic "100% renewable" tariffs (weaker).

8. Allocated emissions (Supply Chain questionnaire only)

The question your customer actually cares about: "How much of your total emissions are attributable to sales to us?"

The mechanical answer is a revenue-allocation calculation: (Total Scope 1+2 emissions) × (revenue to this customer ÷ total revenue). CDP accepts this. If you have a more accurate activity-based allocation (actual units shipped, actual factory time), that scores higher.

How long does it take the first time?

For a UK SME completing the CDP Supply Chain questionnaire for the first time, expect:

2-3 days gathering source data (utility bills, fuel receipts, fleet mileage, HR commuting data)
1-2 days running emissions calculations and verifying totals
2-3 days drafting answers to the narrative questions (governance, strategy, risks, targets)
1 day internal review and submission

That is a working week the first time. In year two it drops to 2-3 days if your answers and evidence are kept organised. In year three, if you maintain a structured fact library, responding to CDP becomes a day's work — because 70-80% of the answers repeat.

The ESG Questionnaire Time Calculator will give you a rough estimate in your own figures based on question count and evidence complexity.

The hidden pattern: CDP answers repeat across every sustainability questionnaire you will ever answer

This is the thing most UK SMEs discover the hard way. By the time a company has answered CDP once, answered an EcoVadis scorecard (see our EcoVadis preparation guide), filled in their bank's sustainability-linked loan questionnaire, and drafted a VSME baseline (see our VSME standard explained), they have typed the same 40 facts four times into four different formats:

Total employees
Total revenue
Scope 1 emissions in tCO₂e
Scope 2 emissions
Electricity purchased (kWh)
Gas purchased (kWh)
Business travel mileage
Company vehicle count and types
Waste produced and diverted
ISO 14001 status
Modern slavery statement status
Board oversight of sustainability
Climate target (base year, target year, percentage)
Policy documents (environmental, H&S, anti-bribery)

The questions are asked differently. The underlying facts are identical. This is the core observation behind AnswerVault: instead of rewriting these 40 facts into each new questionnaire format, keep them once in a structured vault, version them as your business changes, and pull them into the current questionnaire in minutes.

Frequently asked questions

Is CDP mandatory for UK companies? No. CDP is a voluntary international disclosure system. UK statutory climate reporting is covered by different regimes — mainly SECR and ESOS. CDP becomes effectively mandatory when a large customer requires it as a condition of supply.

How is CDP different from EcoVadis? CDP focuses exclusively on environmental disclosure (climate, water, forests) and produces a numerical score for benchmarking. EcoVadis covers environment, labour, ethics, and sustainable procurement across 21 criteria and produces a medal rating (Bronze, Silver, Gold, Platinum). Many UK SMEs answer both. See our EcoVadis assessment preparation guide.

How is CDP scored? CDP scores disclosures on a letter scale: D- (disclosure stage) through A (leadership). Most SMEs starting out score in the C-D range, reflecting early-stage disclosure — CDP does not publish SME-specific score distributions, but D (disclosure) through C (awareness) is where first-time SME filers typically land. A consistent upward trajectory over 2-3 years is what most buyers actually look for, not a single letter grade.

What evidence do I need to attach? CDP lets you upload supporting evidence but does not mandate it for most questions. Attach evidence for: emissions calculation methodology, energy consumption data, any third-party verification, and policy documents referenced in narrative answers. Our guide to organising ESG evidence covers how to keep this manageable across years.

Can I re-use last year's answers? Yes — and you should. CDP saves prior submissions in your account. The challenge is usually not lack of access; it is that the questions moved, wording changed, or the colleague who answered last year has left. Keeping a source-of-truth fact vault outside the CDP platform solves this.

The tl;dr for UK SME sustainability leads

CDP is voluntary nationally but often practically mandatory commercially
The Supply Chain Climate questionnaire is the most common version UK SMEs receive
Start with 2-3 days budgeted for data gathering, not 2-3 hours
Use the UK government conversion factors — they are the accepted default
70-80% of CDP answers repeat across every other sustainability questionnaire you will ever receive — store them once, reuse them everywhere

This is exactly what AnswerVault is built for. If you want to see how a structured vault of reusable ESG facts works in practice, start a free 14-day trial — no credit card needed, 40 starter facts preloaded.

Sources

CDP — Carbon Disclosure Project
CDP — Companies disclosure programme
CDP — Supply Chain programme
CDP — Scoring methodology
Greenhouse Gas Protocol Corporate Standard
UK government greenhouse gas conversion factors (2025)
Science Based Targets initiative (SBTi) — Companies taking action
UK Government guidance: Measuring and reporting environmental impacts
This article provides general guidance for UK SMEs on sustainability questionnaire processes. It is not legal, accounting, or tax advice. CDP requirements change annually — consult CDP directly for current questionnaire content.