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Customer sustainability requirements: what your buyers can ask of you
Most mid-sized UK suppliers are now asked for one or more of seven things: an EcoVadis rating, Scope 3 data, a science-based target, a Carbon Reduction Plan, ISO 14001, other supplier questionnaires or a modern slavery statement. Here is who asks, how often, and what each takes.
| Requirement | Who usually asks | How often | What it takes |
|---|---|---|---|
| EcoVadis rating | Large private customers, often multinationals with supplier sustainability programmes | Every 12 months | Policies, evidence and a questionnaire, scored by EcoVadis analysts |
| Scope 3 data | Customers with their own emissions targets or reporting duties | Yearly | A measured carbon footprint, split per customer or per product |
| Science-based target | Customers with SBTi targets of their own | Set once, reported yearly | A footprint, a reduction target and validation by SBTi |
| Carbon Reduction Plan | UK central government buyers, for major contracts | Kept current; check each tender | A published plan in the government format, signed off by a director |
| ISO 14001 | Tender frameworks in construction, facilities, engineering and the public sector | Audited yearly, recertified every 3 years | An environmental management system and an external certification audit |
| Other questionnaires | Customers using CDP, Sedex, IntegrityNext, Achilles or their own forms | Mostly yearly | The same evidence base, reformatted each time |
| Modern slavery statement | The law, for turnover of £36m or more, and customers checking it | Every financial year | A board-approved statement published on your website |
EcoVadis rating
EcoVadis is the request suppliers meet most often. It scores four themes (environment, labour and human rights, ethics, sustainable procurement) from the policies and evidence you upload. The scorecard lasts 12 months, so the request comes back every year.
It is a rating, not a certificate. There is no pass mark: your customer compares your score with its own threshold and with your competitors. Our EcoVadis guide explains how the score and medals work.
Scope 3 data
Your emissions are part of your customer's Scope 3. When a large customer reports or sets targets, it needs real numbers from its main suppliers instead of spend-based estimates. The question behind every request is the same: what share of your emissions belongs to us?
Answering it means measuring your own emissions, then splitting them per customer or product in a way you can defend. Once the method exists, it repeats each year at much lower cost.
Science-based targets
More customers now ask whether you have a target validated by the Science Based Targets initiative (SBTi). Smaller companies can use a simpler SME route. Larger ones follow the standard route, which needs a fuller Scope 3 screen. Check SBTi's current SME limits before choosing.
Carbon Reduction Plan (PPN 006)
Under PPN 006, central government departments, their executive agencies and non-departmental public bodies ask bidders for contracts worth more than £5 million a year to publish a Carbon Reduction Plan. The plan commits to net zero by 2050 and reports your current emissions. PPN 006 replaced PPN 06/21 under the Procurement Act 2023. Other public bodies, including parts of the NHS, set their own carbon requirements.
ISO 14001
ISO 14001 is a certified environmental management system, and many frameworks and tenders ask for it outright. Certification needs an external audit, with surveillance audits each year and recertification every three years. If you need both EcoVadis and ISO 14001, plan them together: much of the evidence overlaps.
Other supplier questionnaires
CDP, Sedex, IntegrityNext, Achilles and customers' own spreadsheets all ask versions of the same questions. The efficient answer is one organised evidence base, with a named owner, that every questionnaire draws from.
Modern slavery statement
UK organisations with turnover of £36 million or more must publish a modern slavery statement every financial year, approved by the board and linked from the homepage. Customers check it, and EcoVadis looks for the human rights due diligence behind it.
What this could earn you. Each requirement makes you gather energy, materials, waste and supplier data in one place. That same data often shows where money is leaking out of the business.