Agricultural soils have lost a large share of their original carbon through ploughing and intensive farming. Putting some of it back is one of the cheapest forms of carbon removal on paper, and in January 2026 Microsoft agreed to buy about 2.85 million soil carbon credits over twelve years from one programme alone.
Soil carbon credits pay farmers for practices that rebuild soil organic carbon, but the credit is only as good as the measurement behind it and the commitment to keep the practices going. This article explains how the credits are earned, how they are measured, where the quality bar sits since the ICVCM approvals of October 2025, and what to check before buying.
How farmers earn soil carbon credits
A farmer joins a programme and changes one or more practices on enrolled fields:
cover crops between main crops, so living roots feed the soil year-round;
reduced or no tillage, so less soil carbon is broken down;
more diverse crop rotations, including perennials;
better nutrient management, which also cuts nitrous oxide emissions;
improved grazing management on pasture.
The programme developer measures the change in soil carbon against a baseline of continued normal practice, and a registry issues credits after verification. In Indigo’s programme, which supplies the Microsoft deal, issuance typically takes about two years from the first practice change, and 75% of credit revenue goes to the farmers (ESG Dive).
Why measurement is the hard part
Soil carbon varies a lot within a single field and changes slowly, by small amounts relative to the carbon already there. Methodologies combine three tools:
soil sampling at the start and at later points, to a set depth;
biogeochemical models that estimate the change between samples;
remote sensing to confirm the practices on the ground.
The uncertainty this leaves is deducted from the credits. That is why the measurement rules decide credit quality more than the farming practice itself (MRV for carbon credits).
Where the quality bar sits now
In October 2025 the ICVCM approved the first two soil methodologies for the CCP label, each with conditions (ICVCM):
Methodology | Approved for the CCP label when |
|---|---|
Climate Action Reserve, US Soil Enrichment Protocol v1.1 | the farmer signs a commitment of at least 40 years, and the practices are not rotational or intensive grazing |
Verra VM0042 Improved Agricultural Land Management v2.2 | soil carbon is measured with an allowed technique other than digital soil mapping, which has not been assessed |
Those conditions are a practical checklist for any soil credit: how long is the commitment, how is the carbon measured, and which practices are included (Core Carbon Principles). Credits from earlier VM0042 versions have not been assessed. Verra is consulting on a version 3.0.
Permanence: the main risk
Soil carbon is reversible. If a farm returns to intensive ploughing, much of the stored carbon can be released within years. Soils also approach a new balance after a few decades, so gains slow down over time. Programmes deal with this through long monitoring periods, permanence agreements with farmers and buffer pools (carbon credit permanence).
Under SBTi’s Corporate Net-Zero Standard V2.0, soil carbon counts as a short-lived removal, alongside forests. That makes it useful for the short-lived share of a removal portfolio, not for the long-lived share that SBTi increases toward 2050 (carbon dioxide removal explained).
Tip from Bernard de Wit, Founder of Regreener: “Ask what happens to the credits if a farmer leaves the programme in year eight. A good answer names the contract term, the buffer and who replaces the lost tonnes. A vague answer tells you the permanence risk sits with you.”
Soil carbon in Europe
In the EU, soil carbon falls under carbon farming in the EU’s Carbon Removals and Carbon Farming certification (CRCF), which sets certification rules and a minimum monitoring period of five years. For European food and drink companies, soil carbon programmes in their own supply chain are often more relevant as insetting than as credits bought on the market (insetting vs offsetting).
“Soil carbon is where the farming story is strongest and the measurement is hardest. That is why we look for programmes that measure the soil, keep a buffer for losses and tie farmers in for years. We have several in Europe, from German arable farms to Dutch grassland, and we place them next to more durable removals, not instead of them.”
Bernard de Wit, Founder of Regreener
Comparing removal types?
See how soil carbon compares with the forest, biochar and other removal projects in our portfolio.
