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    CDP reporting explained: how scoring works and why the data is the hard part

    CDP reporting means answering CDP's annual environmental questionnaire, usually because an investor or a large customer asked you to. Responses are scored from D- to A across four levels. In the 2026 cycle the scoring deadline was 16 September, and final responses close in the week commencing 26 October.

    Last updated 27 October 2026 · By Tom Wilford, Founder, Ella

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    What is CDP reporting?

    CDP is an international non-profit, founded in 2000 and formerly called the Carbon Disclosure Project, that runs a global environmental disclosure system. CDP reporting is the work of filling in its questionnaire through the CDP portal, covering climate change and, where relevant to your sector, forests and water security. Your answers are then scored and shared with whoever requested them. It is voluntary in the legal sense. In practice, when a major customer or your investors ask, it rarely feels optional. CDP's own figures show over 22,100 businesses disclosed in 2025, representing nearly two thirds of global market capitalisation, and over 4,400 of them were doing it for the first time.

    Who asks for CDP reporting, and why have you been asked?

    Most companies arrive at CDP because someone sent them a request. There are three main routes, and knowing which one you came through tells you who will read the response and how much the score matters. You can also disclose without being asked, as a self-selected company.
    Who asks for CDP reporting, and why have you been asked?
    Request routeWho sends itWhat it usually means for you
    Supply chainA customer that is a CDP Supply Chain memberYour buyer wants your emissions data for their own Scope 3 and supplier scoring. In 2025, 270+ major buyers asked around 45,000 suppliers to disclose.
    Capital marketsInvestors who are CDP signatories, via a letter to the boardInvestors use the data in their analysis. In 2025, 640 investors with US$127 trillion in assets asked CDP to collect data. Ignoring an investor request earns an F.
    Banks and initiativesLenders or initiatives you belong toOften linked to financing terms or membership commitments.
    Self-selectedNobody, you choose to discloseA way to build a track record before a customer or investor asks.

    How CDP scoring works

    Companies are scored on four levels, each with two grades. Scoring is done by accredited partners trained by CDP, by sector, and the methodology is aligned with TCFD and IFRS S2. Management and Leadership points are weighted by how important each issue is for your sector. One detail people miss: scores are based on what is in your response. CDP says significant actions not mentioned in the response are only considered at the Leadership level. If you did the work but cannot evidence it in the questionnaire, it mostly does not count. The top of the range is small. CDP's 2025 A List, published on 8 January 2026, named 877 companies, about 4% of the nearly 20,000 companies scored.
    How CDP scoring works
    LevelGradesWhat it rewards
    DisclosureD- or DCompleteness of your reporting
    AwarenessC- or CUnderstanding how environmental issues affect the business
    ManagementB- or BEvidence that you are managing your environmental impact
    LeadershipA- or ABest-practice strategy and action
    Not disclosedFRequested by investors but no response, or not enough information to score

    CDP reporting deadlines for 2026

    For the 2026 cycle, CDP set the scoring deadline at 16 September. Responses or edits submitted after that are accepted but not scored. The final response deadline falls in the week commencing 26 October, after which the questionnaire closes and no edits are allowed. If you are reading this in late October 2026, that window is closing now, so the useful thing to do is plan for 2027.
    CDP reporting deadlines for 2026
    MilestoneDateWhat it means
    2025 A List published8 January 2026Last year's scores and A List made public
    2026 scoring deadline16 September 2026Submit by this date to be scored
    2026 final response deadlineWeek commencing 26 October 2026Questionnaire closes, no further edits

    Full corporate questionnaire or SME questionnaire?

    CDP runs two company questionnaires. The full corporate questionnaire covers climate change, forests and water security, with a setup step that decides which modules and questions apply to your sector. CDP provides mappings to IFRS S2, GRI and TNFD, so work you do for one framework can be reused. The SME questionnaire is shorter. Nearly 11,000 smaller companies used it in 2025, its second year. CDP's scoring page notes that in 2024 the highest score available to an SME was SME B, which is worth knowing before you promise the board an A. Before you start, confirm the submission lead and whether an administrative fee applies, because CDP asks you to choose and pay it before you can submit.

    Why the questionnaire is the easy part

    Here is the opinion, and it comes from a lot of sales calls with sustainability leads. Nobody tells us the CDP questions are confusing. They tell us they are one person, the data sits with ten other people, and the request landed with a deadline that did not care about their holiday. One of the first questions we hear on almost every call is some version of: what do you actually need from us to get started? That is the right question. The narrative answers in CDP can be drafted in an afternoon by anyone who knows the business, and general AI assistants are decent at it. What they cannot do is email the facilities manager for the gas bills, notice that two sites are missing March, and keep asking until the numbers arrive. Because CDP scores on what is evidenced in the response, a gap in the data is a gap in the score. The table below is roughly where the data hides.
    Why the questionnaire is the easy part
    What CDP asks aboutWhere the data usually livesWho you end up chasing
    Scope 1 fuel and gasSupplier invoices, fuel cards, meter readsFacilities, site managers, fleet
    Scope 2 electricityEnergy bills, landlord recharges, REGO or tariff evidenceFacilities, finance, landlords
    Scope 3 categoriesSpend data, supplier responses, travel bookingsProcurement, finance, travel provider
    Targets and transition planBoard papers, reduction plansLeadership team, company secretary
    Governance and riskRisk registers, policies, committee minutesRisk, legal, HR
    Water and forests (if in scope)Utility bills, sourcing recordsOperations, procurement

    How to prepare for CDP 2027 starting now

    The companies that find CDP manageable treat it as a by-product of a data process that runs all year. The summer scramble is optional. A practical sequence: 1. Read last year's score report and list the questions where you lost points for missing or unevidenced data. 2. Map every data point to a named person who owns it. 3. Set collection on a quarterly cycle so invoices and meter data come in while people still remember where they put them. 4. Keep the source document attached to every number, so verification and your own review move quickly. 5. Reuse the same dataset for SECR, your carbon reduction plan and customer questionnaires, so CDP is not a separate exercise. 6. Draft narrative answers from the data once it is in, then review them against the scoring guidance before the September scoring deadline.

    What CDP reporting software should do, and where Ella fits

    If you are comparing CDP reporting software or carbon accounting software, judge it on the collection side first. Can it request data from colleagues and suppliers and follow up without you? Can people drag and drop an invoice instead of typing numbers into a form? Does every figure keep a link to its source? A tidy dashboard on top of incomplete data still produces a D. Ella is AI-native ESG software built as an agent. Its Carbon module covers CDP alongside SECR and carbon reduction plans. It chases colleagues by email for the data, reads uploaded bills and invoices, pulls from integrations and surveys, cleans what comes back and keeps a source on every number. Your team reviews the drafted responses before anything is submitted through the CDP portal. We built it for sustainability teams at large and fast-growing companies where one or two people carry the reporting for the whole business.

    How Ella helps

    Carbon accounting software

    Collect Scope 1, 2 and 3 data, calculate emissions and prepare CDP and SECR reporting with a source on every number.

    ESG reporting software

    One dataset for CSRD, VSME, CDP and customer questionnaires, collected and cleaned by an AI agent.

    ESG RFP automation

    Answer customer sustainability questionnaires and tenders from your existing ESG data in hours.

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    Frequently Asked Questions

    What is CDP reporting?

    CDP reporting is the process of completing CDP's annual environmental questionnaire on climate change and, where relevant, forests and water security. Companies usually respond because an investor or customer requested it. CDP then scores the response from D- to A and shares it with the requesters.

    Is CDP reporting mandatory?

    No law requires it. It is voluntary, but requests from investors and large customers carry real weight. If CDP capital markets signatories request your disclosure and you do not respond, you receive an F for each environmental issue you were asked about.

    When is the CDP deadline in 2026?

    The 2026 scoring deadline was 16 September 2026. Responses after that are accepted but not scored. The final response deadline is in the week commencing 26 October 2026, after which the questionnaire closes and no edits are allowed.

    How does CDP scoring work?

    There are four levels: Disclosure (D- or D), Awareness (C- or C), Management (B- or B) and Leadership (A- or A). Accredited scoring partners score responses by sector, using a methodology aligned with TCFD and IFRS S2. Scores are based on what is in your response.

    What is a good CDP score?

    A B or B- shows you are actively managing your environmental impact, which is a solid result for most companies. An A is rare: 877 companies made the 2025 A List, about 4% of the nearly 20,000 companies scored. SMEs using the SME questionnaire were capped at SME B in 2024.

    How much does CDP reporting cost?

    CDP may charge an administrative fee, which you choose and pay in the portal before submitting. Current amounts are on CDP's website. The bigger cost is usually internal time spent collecting data from colleagues, suppliers and invoices.

    What is the difference between CDP and SECR?

    SECR is a UK legal requirement for quoted companies, large unquoted companies and large LLPs to report energy use and emissions in their annual report. CDP is a voluntary global questionnaire requested by investors and customers. The same emissions data can feed both.

    Can AI help with CDP reporting?

    Yes, in two ways. General AI assistants can help draft narrative answers. ESG software built as an agent, such as Ella, can also collect the underlying data by chasing colleagues, reading invoices and keeping a source on every number, which is where most of the time goes.

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