Best carbon accounting software for UK tenders in 2027

In short

• A UK bid needs a document in a prescribed format, not a dashboard. Buy for the output.
• Of the seven tools here, two publish a price. The rest quote after a call, which costs you bid time.
• The NHS asks for more than PPN 006 does, so check which buyer you are actually selling to.

Seven carbon platforms realistically turn up on a UK bid team's shortlist, and they separate on three checkable facts: whether they name PPN 006 as an output, whether they publish a price, and how fast you can start without a sales call. What a UK tender needs is narrow. A carbon reduction plan covering scope 1, scope 2 and five named scope 3 categories, refreshed every twelve months, in a format the buyer recognises. The tool that wins is the one that produces that document before your submission deadline, not the one with the longest feature list.

We make one of the seven. Everything below about a rival comes from that vendor's own public pages, read on 27 August 2026, and everything about us comes from our platform page or from customers on G2 who we cannot edit.

What does a UK tender actually ask you to produce?

Two obligations dominate, and they are not the same size.

PPN 006 applies to UK central government contracts above GBP 5 million a year. It wants a carbon reduction plan covering scope 1, scope 2 and five named scope 3 categories, refreshed every twelve months. It is a published document with a required shape. Our PPN 006 checklist goes through it line by line.

The 2027 NHS carbon reduction plan requirement applies to NHS suppliers from April 2027, for contracts at or above GBP 5 million a year and for all new NHS frameworks regardless of value, and it asks for more than PPN 006 does. Targets, emissions and a carbon reduction plan covering global emissions and every relevant scope 3 category, rather than the five categories PPN 006 names. This is a separate thing from NHS Evergreen, the voluntary supplier self-assessment tool that is not itself a scored procurement requirement, though the two get merged in casual use. If you sell to both, size your data collection against the 2027 CRP requirement, because it is the larger one. We break down the Evergreen assessment separately in the NHS Evergreen supplier assessment.

The distinction matters when you buy. A tool sized for PPN 006 may not carry you into an NHS bid a year later, and finding that out in the week before submission is the expensive version of this discovery.

Which tools are actually in scope for a UK bid team?

Seven, with the facts we could verify on their own public pages on 27 August 2026.

Two notes on how to read that table. "Not verified" means we did not find the claim on a public page on 27 August 2026, not that the tool cannot do it. And a G2 rating built on nine reviews and one built on twenty-seven are not the same evidence, whatever the decimal says.

What separates these tools on facts you can check?

Three things, and only three, are worth arguing about at shortlist stage.

Whether the output exists as a document. A dashboard showing your footprint is not a carbon reduction plan. Ask any vendor for a real example of the artefact you have to submit, redacted if necessary. If they show you a chart instead, you have your answer.

Whether the price is knowable before you commit bid time. EcoHedge publishes GBP 990 a year for Express Growth and a free forever Lite tier, read on their pricing page on 27 August 2026. Hedgehog publishes Pro from EUR 1,200 a year on its G2 profile. The other five quote after a call. That is a legitimate way to sell enterprise software, and it costs a bid team two weeks it does not have.

Whether the emission factor library reaches your spend. EcoHedge claims 277,000 or more emission factors on its comparison page, read on 27 August 2026. Hedgehog publishes 20,000 or more spend-based and activity-based factors plus the ability to add your own organisation-specific or supplier-specific data. Their count is larger and we will not pretend otherwise. Whether a larger count helps depends entirely on whether the extra factors cover the categories you actually buy.

Which one fits which situation?

Match the tool to the bid, not to the brochure.

A UK SME whose ledger sits in Xero, QuickBooks or Sage, bidding on one PPN 006 contract. EcoHedge is the straightforward answer. It publishes native one-click integrations with those three systems and names SECR, PPN 006 and HMRC categories as built-in outputs, per its comparison page read on 27 August 2026. If the integration is the thing standing between you and a number, buy the integration.

A company bidding in both the UK and the Netherlands. You need PPN 006 and the CO2-Prestatieladder from the same inventory, which narrows the field quickly. Ask each vendor to show both outputs.

A mid-market group with several legal entities and an NHS bid in 2027. Every relevant scope 3 category and global emissions is a data collection programme, not a software purchase. Whatever you buy needs multi-entity handling and a credible route from spend data to supplier data over two or three years.

A large enterprise with an assurance requirement and a corporate ESG report to file. The broad platforms are on your list for a reason. Expect a quote, expect it to be driven by entities and seats, and budget the assurance separately because it is rarely in the licence.

What does Hedgehog do for UK bids, and where is it the wrong choice?

The platform names PPN 006 and the CO2-Prestatieladder as reporting outputs and names CSRD, SECR and SB253 under legislation. It guides you through GHG Protocol setup, inventory building and data upload with an AI assistant, carries over 20,000 spend-based and activity-based factors, lets you add supplier-specific data, and handles multiple entities with roles for data owners, auditors and managers. Free account with no sales call. Pro from EUR 1,200 a year.

Two honest limits, both from paying customers on a public page.

It is not a broad ESG suite. A Mid-Market customer rated Hedgehog 3.5 out of 5 on G2 in June 2026 and said that for broader ESG data and reporting the platform is less complete, with no data source management feature and no decarbonisation target monitoring. If your tender question set is genuinely an ESG questionnaire rather than a carbon one, weigh that seriously.

Loading the data is the work. A Small-Business customer said on G2 in August 2026 that once the data is loaded everything works perfectly, and getting it loaded is the challenging part. That is true here and it is true of every tool in this table. Nobody produces a credible scope 3 figure from a cold start in a day, whatever the marketing says.

What should a bid team do next?

Start from the submission date and work backwards.

Find out which obligation you are answering, PPN 006 or the NHS assessment, because the second is materially larger. Then ask your two or three shortlisted vendors for the same three things: an example of the finished document, a price for one entity and three users with no services, and what happens to that price in year two. The vendors who answer in a day are telling you something useful about the next twelve months.

If you want a first scope 1 and 2 number before you talk to anyone, you can start a free account and see how bad your data is first. If you would rather work through the shortlist with someone, book a call. We also keep a general guide to choosing carbon accounting software that is not UK specific.

Sources: vendor pricing and comparison pages for EcoHedge, Coolset, Greenly, Watershed, Persefoni and Seedling, each read on 27 August 2026. G2 product profiles read on 27 August 2026. UK Cabinet Office Procurement Policy Note 006 and its Technical Standard, and NHS England's 2027 NHS carbon reduction plan requirements and Evergreen sustainable supplier assessment, all read 17 September 2026. Hedgehog platform and Hedgehog on G2. Vendors change their pages often, so re-check any figure before you rely on it in a bid.

Facts on this page were last verified on 2026-09-17.