In short
- Six pricing models are in use, so two quotes are almost never comparable as written.
- Normalise to a three-year total for one fixed scenario, then divide by three.
- The cheaper headline is frequently the more expensive contract.
Carbon accounting software is sold on at least six different pricing models, which is why two quotes for the same requirement rarely arrive in a form you can compare. One vendor prices per seat and entity, another per tonne of CO2e, another bundles consultant days into a flat fee. The only way to compare them is to convert each quote into a single number: the total cost of one fixed scenario over three years, divided by three. This page sets out the models, the normalisation method, and a worked example where the cheaper headline turns out to be the more expensive contract.
Two things this page is not. It is not the pricing census, where we went looking at eleven vendors on 27 August 2026, reached eight pricing pages, and found that only EcoHedge published plan prices. It is not the guide to what a vendor counts as an entity. This one is about the arithmetic you do after the quotes land.
Which pricing models are actually in use?
Six, often two or three at once inside a single quote.
| Model | What drives the bill | What it hides |
|---|---|---|
| Per user seat | Number of logins | Whether read-only users, data owners and auditors are billable |
| Per entity | Count of legal, reporting or site entities | Each vendor defines entity differently, and dormant entities often count |
| Per emissions volume | Tonnes of CO2e in your inventory | Your bill rises as your scope 3 gets more complete |
| Per supplier engaged | Suppliers you contact for primary data | The cost scales with the ambition of your programme, not your size |
| Bundled services | A flat fee including a number of consultant days | What happens when the days run out, and the day rate after that |
| Quote only | Negotiation | Everything, until you ask |
The per-emissions-volume model deserves a note, because it is the one that surprises buyers most. If you price on tonnes, then improving your scope 3 coverage from four categories to nine increases your licence cost. You are being charged for doing the job better. That may still be the right product for you, but you should model year three on a complete inventory rather than on the partial one you have today.
The per-supplier model has the same shape. Engaging forty suppliers for primary data is a good idea and it is a line item.
Why will a vendor not simply give you a number?
Three reasons, and only the third is a problem for you.
The pricing genuinely varies with the shape of the buyer, so a single list price would be wrong for most of the market. A large share of the deal is people rather than software, and services are quoted rather than listed. And a call before a price lets the vendor size the account before it commits, which is legitimate and costs you two weeks.
The market position is easy to verify yourself, with one caveat worth stating: of eleven vendors we went to on 27 August 2026, three pages returned a 404, so we can report on eight and say nothing about the other three. Of those eight, we read the pricing pages of Coolset, Greenly, Watershed, Persefoni and Seedling and found no numeric plan price on any of them. Two of those five are still worth a look before you book a call, because no published price is not the same as no way in: Persefoni Pro is offered free, and Seedling carries a Start for Free route, neither with a published plan price behind it. EcoHedge, read the same day, publishes a free Lite tier and Express Growth at GBP 990 a year on its pricing page, with several other figures on the page whose tier mapping is not obvious. Hedgehog publishes a free account and Pro from EUR 1,200 a year on our G2 profile.
So for most vendors you will be comparing quotes, not prices. Which makes the normalisation the whole exercise.
What should you normalise to?
One scenario, three years, one currency, everything included. Write the scenario down before the first call and send the same paragraph to every vendor.
A usable scenario states five things: how many entities and on what definition, how many users of each type, roughly how many tonnes of CO2e and how many scope 3 categories, how many suppliers you intend to engage, and how much help you want in year one. That last one is what makes bundled quotes comparable to unbundled ones.
Three years rather than one, because carbon reporting is an annual routine and first-year discounts are standard. A quote that is cheapest in year one and most expensive across the term is the most common trap in this category, and it is invisible in a side-by-side of headline prices.
What does a worked normalisation look like?
Here is the arithmetic on a scenario of three entities, two full users, six data owners uploading their own data, roughly 12,000 tonnes CO2e, forty suppliers to engage, and a first year with onboarding support.
The figures below are invented to demonstrate the method. They are not market prices and should not be quoted as such.
| Line item | Quote A | Quote B |
|---|---|---|
| Headline price | EUR 7,500 a year | EUR 12,000 a year |
| Year 1 licence | 9,000, onboarding included | 12,000 |
| Year 2 licence | 7,500 | 12,000 |
| Year 3 licence | 7,500 | 12,000 |
| Six data owner seats, three years | 4,500 | Included |
| Three entities, three years | Included | Included |
| Supplier engagement, three years | 18,000 | Included |
| One-off onboarding | Included | 6,000 |
| Three-year total | 46,500 | 42,000 |
| Normalised annual cost | 15,500 | 14,000 |
Quote A is advertised at EUR 7,500 a year and Quote B at EUR 12,000. Over the term that a carbon reporting programme actually runs, A costs about eleven percent more.
Nothing here is dishonest on either side. A is a modular product with a low entry point and priced add-ons. B is an all-in product with a high entry point. The headline told you almost nothing about which was cheaper for your situation, and would have told you the opposite for a company with two users and no supplier programme.
That is the point of normalising. Run your own numbers through both structures rather than trusting either headline.
Which costs sit outside both quotes?
Four, reliably, and together they often exceed the licence.
Your own data work. The largest cost in most carbon programmes is internal time spent collecting and reconciling data. No vendor quotes it and every vendor knows it exists.
Assurance. If your figure gets externally verified, that is a separate engagement with a separate firm, and for a mid-sized group it is frequently larger than the software line.
Product footprints. An LCA, an EPD, an MKI or a PCF is a project, not a subscription. If a customer has asked for a per-product number, price that separately from the start.
Year four. Ask what the renewal looks like after the initial term. A three-year normalisation with an unknown year four is still better than a headline, but the question is free to ask.
What questions force a comparable answer?
Send these in writing, with your scenario attached, and you compress the process by a fortnight.
- What is the total cost of my exact scenario in year one, year two and year three?
- Which of seats, entities, emissions volume and suppliers engaged changes that number, and by how much per unit?
- Are read-only users, data owners and auditors billable seats?
- What is included in onboarding, how is it measured, and what is the rate once it is used up?
- What happens to the price when my scope 3 coverage doubles?
- What is the renewal price after the initial term?
If a vendor will not answer the first question in writing, that is itself a comparison result. We go through the wider selection criteria in choosing carbon accounting software for SMEs.
Where does Hedgehog sit, and what do we not do?
We are one of the vendors in this market, so weigh this section accordingly.
Hedgehog publishes a free account with no sales call and Pro from EUR 1,200 a year, priced on user seats and business entities, and that figure is on our public G2 profile rather than behind a call. The platform is rated 4.7 on G2 from nine reviews. There is no per-tonne charge and no per-supplier charge in that structure, which makes it simpler to normalise than most, and it also means the honest comparison is against the modular quotes rather than the all-in ones.
Two limits that belong in any pricing comparison, both from paying customers on a public page.
Few integrations today. A customer named more integrations with other software as the single thing they would change, on G2 in June 2026. If part of your business case is automated data pulls that remove internal effort, discount that saving when you model us.
Not a broad ESG suite. A customer rated us 3.5 out of 5 in June 2026 and said that for a broader ESG data and reporting platform this one is less complete, with no data source management feature and no decarbonisation target monitoring. If you are buying one system for all of ESG, a cheaper carbon licence is a false economy, and the distinction between the two categories is worth reading first in ESG reporting software versus carbon accounting.
What should you do first?
Write the scenario paragraph. Five lines, one page, sent identically to every vendor on your list. It is the single highest-return hour in the whole procurement, because it converts six sales conversations into six comparable answers.
Then build one entity for free before you sign anything, so that your scenario is based on how your data actually behaves rather than on how you hope it behaves. You can start an account without a call, or book a meeting if you would rather talk the structure through.
Method: eleven competitor pricing pages were attempted on 27 August 2026 and checked for a numeric price. Eight were reached and are reported here; three returned a 404 and are reported as unreached, not as quote-only. Vendors change pricing often, so re-check before relying on any figure. Sources: Hedgehog on G2 and the EcoHedge pricing page, both read on 27 August 2026, together with the Coolset, Greenly, Watershed, Persefoni, Seedling, Normative and Sweep pricing pages read the same day. Page verified 16 September 2026. The worked example uses invented figures to demonstrate the arithmetic.
Facts on this page were last verified on 2026-09-16.
