The Soil Carbon Method —
a plain English guide
The Australian Soil Carbon Method allows landholders to earn Australian Carbon Credit Units (ACCUs) by increasing the amount of carbon stored in their agricultural soils.
In simple terms, the method rewards measured increases in soil organic carbon that result from changes in land management — provided those changes meet strict integrity, measurement and reporting rules.
This page explains how the method works in practice, in plain English.
What the Soil Carbon Method actually does
Under the ACCU Scheme, soil carbon projects can earn credits when:
Soil organic carbon levels increase over time
Those increases are measured and verified
The changes are additional (they wouldn’t have happened anyway)
The carbon is maintained over the required permanence period
Each ACCU represents one tonne of carbon dioxide equivalent (t CO₂-e) stored in soil.
The method is formally called:
Estimation of Soil Organic Carbon Sequestration using Measurement and Models (2021)
It is administered by the Clean Energy Regulator (CER) under the ACCU Scheme.
What landholders must change
To be eligible, landholders must make a material change to land management that is reasonably expected to increase soil carbon.
Examples may include changes to:
Grazing management and groundcover
Cropping systems and rotations
Pasture species and diversity
Nutrient and input strategies
Soil disturbance practices
Organic matter inputs (where eligible)
Not every practice change leads to measurable increases — outcomes depend heavily on soil type, climate, rainfall, starting condition and management history.
How soil carbon is measured
Soil carbon projects rely on baseline sampling and repeat measurement.
In practice this means:
Baseline sampling
Soil samples are taken at the start of the project to establish starting soil carbon levels.
Ongoing sampling and/or modelling
Soil is resampled over time to measure changes, often combined with approved soil carbon models.
Laboratory analysis
Samples must be analysed using approved laboratory methods and quality controls.
Emissions adjustments
Changes in on-farm emissions linked to management (for example livestock, fertiliser, lime or tillage) must be factored into the final abatement calculation.
You are credited for net increases in soil carbon, adjusted for associated emissions and method discounts.
Key integrity and discount factors
Soil carbon projects are subject to several built-in discounts and buffers to protect scheme integrity. These include:
Withheld credits in early years
A portion of credits may be held back in initial reporting periods.
Risk of reversal buffer
A buffer to account for potential future carbon loss.
Statistical confidence requirements
Only changes that meet strict confidence thresholds are credited.
Permanence obligations
Projects must maintain carbon for the nominated permanence period (generally 25 or 100 years).
These factors mean not all measured increases convert directly into ACCUs.
Reporting, audits and compliance
Soil carbon projects must:
Submit regular project reports
Maintain detailed records
Undergo scheduled independent audits
Comply with Land Management Strategy (LMS) requirements
Demonstrate ongoing eligibility and integrity
This makes soil carbon a long-term regulatory commitment, not a one-off activity.
Why some projects succeed — and others don’t
In practice, soil carbon outcomes vary widely.
Success depends on:
Rainfall and climate reliability
Starting soil carbon levels
Soil type and depth
Management history
Ability to maintain practice changes
Seasonal variability
Sampling design and variability
This is why some projects generate meaningful credits — while others see limited or highly variable results.
How CMS helps landholders navigate the Method
Carbon Management Services does not start with the method.
We start with your whole-of-farm context, then assess:
Whether soil carbon is technically viable
Whether it stacks up commercially
How it fits with productivity goals
How it interacts with emissions and other methods
Whether alternative or complementary pathways make more sense
This helps landholders avoid investing time and money in projects that may not deliver the outcomes they expect.
The bottom line
The Soil Carbon Method can be a powerful tool — when it fits your land, system and long-term strategy.
It is also complex, long-term and highly variable.
Understanding how it works in practice is essential before committing.
Talk to CMS about whether the Soil Carbon Method makes sense for your land.
We’ll assess soil carbon as part of a broader whole-of-farm low-carbon strategy — so decisions are based on reality, not assumptions.