background image

High-quality carbon offsets: a buyer's guide

author image

By illuminem

· 6 min read

This article is part of illuminem's Carbon Academy, the ultimate free and comprehensive guide on key carbon concepts 

Can carbon trading systems reduce global emissions, or are they little more than greenwashing?

The market remains complex and full of pitfalls. Engaging in projects that create real impact requires both diligence and maximizing intentional investment. Further, transparent, enforceable standards are critical to defining the differences between high- and low-quality carbon offsets.

This guide is a starting point for a buyer concerned with environmental integrity, and interested in investigating the criteria and selection of high-quality carbon credits.

Even before starting the process of prospecting and analysis, buyers must determine their motivation for buying carbon credits and align with internal stakeholders to share a decisive common goal. Are the credits bought to meet regulatory requirements, achieve corporate sustainability goals, and/or support environmental or social outcomes? 

Understanding carbon offsets

Carbon offsets are measures or projects that compensate for emissions by funding equivalent carbon dioxide savings elsewhere. While the concept may sound straightforward—pay an entity to reduce emissions elsewhere if you cannot reduce your own—the reality is much more complex. At their best, these measures remove carbon effectively and sustainably, taking into consideration both the environmental and social factors. 

Carbon offsets provide various options for compensating for emissions. These options can be broadly categorized into two main groups: those centered on carbon avoidance and reductions, and those focused on carbon removal. Both types of offsets play a role in the broader context of climate change mitigation, and organizations often use a combination of both to address their carbon footprints and contribute to global efforts to combat climate change. 

The purchasing process

Main actors involved: 

1. The carbon project developer ( e.g. Earthshot Labs) 

2. The crediting program (e.g. Verra, Gold Standard)

3. The polluting entity buying carbon credits to claim climate benefits

After determining requirements and comparing providers, the purchasing process starts with a clear ask for credit retailers and collaboration on defining acceptable standards, project types, and additional advantages. 

The evaluation and selection process should be reasonably efficient, considering that credits may only be reserved for short periods and market conditions can rapidly change. Moreover, the purchasing process differs based on the type of carbon credit you purchase (ex-ante, ex-post, pre-purchase). Prepare for agility, specify terms and conditions in advance, and be ready to make quick decisions to secure chosen credits.

Improving the purchasing process

Buyers should systematize their purchasing process to mitigate risks and adapt to changing conditions. The adjustments can involve ongoing education for internal stakeholders, continuous review and updating of purchasing criteria, and assigning specific responsibilities for managing credit purchases. Transparent feedback loops and reporting from credit retailers can improve future transactions and ensure you secure the proper credits at the right price while managing and minimizing risks. 

Organizations, such as VCMI, SBTi, and ICVM have played an important role in creating clearly-defined pathways for the verification process and advocating for high-quality carbon credits.

Selecting high-quality carbon offsets

Experts like John Sterman from MIT propose the following criteria for meaningful carbon offset projects. Known by the acronym AVID+:

  • Additionality: The project should provide carbon sequestration that would not have happened without funding from carbon credits

  • Verifiability: The emission reductions must be measurable and attributable to the project

  • Immediacy: The benefits should occur soon enough to make a difference in climate terms

  • Durability: The benefits should be long-lasting and not easily reversible

  • Plus Factor: Projects should also contribute additional benefits such as biodiversity, community health, or economic development

Assessment and avoiding common pitfalls


Buyers should be wary of projects that offer more marketing claims than actual environmental benefits. If it sounds too good to be true, it likely is. Often, these projects serve broader industrial purposes that prove counterproductive to carbon reduction.

Confirming the real impact of the claimed emissions reductions is essential to verifying the credibility of carbon credits. High-quality projects should transparently showcase their environmental impact through detailed methodologies, monitoring practices, and emission reduction calculations. 

Double Counting and Additionality

Buyers should ensure that multiple actors are not claiming the same offset or that the land is not already protected under existing laws.

Projects must provide clear evidence that their emissions reductions are additional—meaning these reductions would not have occurred without the project's implementation. The additionality aspect ensures that the project contributes genuine environmental benefits.

Lack of Oversight 

Prefer projects under jurisdictions with strict regulatory frameworks to ensure the claimed benefits are real and substantial.

Projects must undergo third-party verification to ensure their emissions reductions are legitimate. This adds a layer of trust and ensures adherence to specific standards. Ensure your chosen carbon offset provider is registered, and each credit has a unique serial number to prevent double counting, i.e., the erroneous claim of the same reduction by multiple entities.


The long-term impact of carbon reduction projects, or their permanence, is crucial. Projects should demonstrate resilience and stability, maintaining their carbon storage or reduction capabilities over time. Stability becomes particularly important in forestry projects, where risks such as fire or disease must be managed to ensure the longevity of carbon storage.

Social sustainability

Engaging with and respecting local communities is critical for the project's impact and acceptance. All high-quality carbon offset projects should adhere to environmental and social frameworks that safeguard the well-being of local communities and ensure long-term sustainable development. 

Implementing these criteria takes time and effort, and each project faces its unique hurdles. Nature-based projects, which require complex quantification of CO2 reductions over various landscapes, can become especially challenging to measure. Time can also affect the criteria's relevance, as projects that were initially additional may only qualify as such for a while. Moreover, verifying additionality is complex. It bears an assumed comparison against a hypothetical scenario where the project did not exist.

Future directions

If the process was not complicated enough, retailers such as GoldStandard and Verra, which issue and verify credits, have faced scrutiny over the quality of credits and have been criticized for issuing 'phantom credits.' Such instances highlight systemic problems in baselining practices, especially within forestry projects. The commercial motivations within the standards-setting landscape also pose risks, as organizations may lower standards to increase credit issuance and revenue.

Despite these challenges, carbon credits can be considered essential for climate action. They are one aspect of many in safeguarding environmental integrity and benefit from the clear intentionality of buyers from the get-go. Additionally, enhancing carbon offsets' effectiveness involves increasing regulation and transparency and fostering competition among rating agencies, systemically similar to financial markets. In the future, we may see a more resilient and credible Voluntary Carbon Market (VCM), but its creation is as much the buyers' responsibility as it is of the sellers.


 Before investing in offsets, conduct thorough research or consult with experts who can assess the credibility and effectiveness of the projects. Reputable third-party certifications and clear, transparent reporting by the project managers are essential indicators of a project's quality. 

There is good reason to approach the carbon market critically and commit to supporting projects that offer verifiable, additional, immediate, and durable benefits to the atmosphere and the communities they serve. With informed and intentional choices, carbon offsets can contribute meaningfully to the global fight against climate change.


Do you have any feedback or do you have a topic you would like us to cover? Click here to get in touch

Are you a sustainability professional? Please subscribe to our weekly CSO Newsletter and Carbon Newsletter

Did you enjoy this illuminem voice? Support us by sharing this article!
author photo

About the author

illuminem's editorial team - delivering the most effective, updated, and comprehensive access to sustainability & energy information.

Follow us on Linkedin, Instagram & Twitter

Other illuminem Voices

Related Posts

You cannot miss it!

Weekly. Free. Your Top 10 Sustainability & Energy Posts.

You can unsubscribe at any time (read our privacy policy)