Not all carbon credits are equal. Some represent real, lasting cuts or removals; others have been counted generously or sold more than once. This section helps you tell the difference before you pay.

Three checks before you buy

  1. Is it real and yours? Every credit has a serial number in a public registry, and Gold Standard’s registry, for example, tracks each one from issuance to retirementSource 2. Ask for the serial numbers and check that the credits are retired in your name. Our guide to how to verify carbon credits shows how, registry by registry.
  2. Is the method credible? The ICVCM’s 10 Core Carbon Principles set a quality threshold, and credits that meet it can carry the CCP labelSource 1. CCP labels explained shows how the label works, and carbon credit ratings covers the agencies that grade individual projects.
  3. Is the seller genuine? Be wary of anyone selling credits as an investment. The FCA warns that investors who bought this way have reported they can’t sell their creditsSource 4. See carbon credit scams.
Registry record · exampleRetired

Serial number

EX-0042-KE-2025-000118–000129

Project
Example cookstove project, Kenya
Kind
Avoidance
Vintage
2025
Quantity
12 tCO₂e
Retired for
Jane Doe
Retired on
4 Oct 2026

Ask any seller for this record.How to verify →

The card above is an example of the record you should be able to find for any credit you buy. It is not a real record.

Why quality matters

The evidence on offsetting is mixed. One review of studies covering almost a billion tonnes of credits estimated that less than 16% of them were real emission reductionsSource 3. Do carbon offsets work? sets out what the research found, the criticism of it, and how standards have responded.

No serial numbers, no proof

If a seller can’t show you serial numbers in a public registry, or won’t retire your credits in your name, you can’t confirm that the tonnes exist, or that they haven’t been sold to someone else.

Our guide to high-quality carbon credits brings all these checks together in one list. For the basics behind these checks, see carbon credit retirement in our Learn section, or start from the guide to buying carbon credits.

Ready to buy? Our buying guides put these checks into practice, from how to buy carbon offsets to where to buy carbon credits.