ISO 14064 is the international standard for quantifying, reporting, and verifying GHG emissions. Learn what its three parts cover and how to get started.
What Is ISO 14064?
ISO 14064 is the international standard that defines requirements and principles for quantifying, reporting, and verifying greenhouse gas (GHG) emissions at both the organizational and project level. Published by the International Organization for Standardization (ISO), it provides a structured framework that helps organizations make their emissions data transparent, consistent, and independently verifiable.
In short: ISO 14064 is a three-part standard covering organizational GHG inventories, project-level emission reductions, and independent verification of both.
First published in 2006 and revised in 2018 (ISO 14064-1:2018, ISO 14064-2:2019, ISO 14064-3:2019), the standard complements GHG Protocol. Where GHG Protocol provides the foundational calculation methodology, ISO 14064 adds the structure and rigor needed for third-party scrutiny. Most organizations working toward audit-ready carbon accounting use both.
This matters because emissions data is increasingly tied to regulatory compliance, trade requirements, and financial disclosures. A number produced through a defined process and confirmed by an independent verifier carries more weight than one sitting in an internal spreadsheet. ISO 14064 bridges that gap.
What Are the Three Parts of ISO 14064?
ISO 14064 is not a single document. It consists of three parts, each addressing a different layer of GHG management. Together, they cover the full cycle from measurement to verification.
ISO 14064-1: Organizational-Level Quantification and Reporting
ISO 14064-1 specifies principles and requirements for designing, developing, managing, and reporting an organization-level GHG inventory. It covers how to define boundaries, identify emission sources, select quantification methodologies, and report results.
Key elements include:
- Defining organizational and operational boundaries (which entities, facilities, and operations are in scope).
- Classifying emissions as direct (Scope 1), energy indirect (Scope 2), and other indirect (Scope 3). The 2018 revision expanded indirect emission categories to align more closely with GHG Protocol’s Scope 3 framework.
- Selecting quantification approaches and emission factors, with clear documentation of assumptions and data sources.
- Establishing a base year and recalculation policy so year-over-year comparisons remain valid when organizational changes occur.
ISO 14064-1 does not prescribe specific emission factors or calculation tools. It sets out principles, including relevance, completeness, consistency, transparency, and accuracy, that any methodology must satisfy. This is why organizations often use GHG Protocol’s Corporate Standard for calculation while structuring the overall program to meet ISO 14064-1 requirements.
ISO 14064-2: Project-Level GHG Reductions
ISO 14064-2 applies to GHG projects, meaning specific activities or interventions designed to reduce emissions or enhance removals. Think of a company replacing fossil-fuel boilers with heat pumps, or investing in a reforestation project. ISO 14064-2 defines how to quantify and report the emission reductions or removal enhancements from such projects.
Core requirements include:
- Establishing a credible baseline scenario (what would have happened without the project).
- Quantifying emission reductions or removal enhancements against that baseline.
- Addressing leakage, meaning unintended emission increases outside the project boundary caused by the project activity.
- Monitoring and reporting project performance over time.
ISO 14064-2 is particularly relevant for organizations that generate or purchase carbon credits, participate in voluntary carbon markets, or need to demonstrate the impact of specific decarbonization investments. The standard provides the methodological backbone for credible project-level claims.
ISO 14064-3: Verification and Validation
ISO 14064-3 specifies requirements for the verification and validation of GHG assertions. In practical terms, this is the part that governs how an independent third party checks whether an organization’s GHG inventory (under 14064-1) or a project’s claimed reductions (under 14064-2) are accurate and complete.
The standard covers:
- The verification process, including planning, evidence gathering, and evaluation.
- Levels of assurance: limited assurance (lower evidence threshold) and reasonable assurance (higher evidence threshold, analogous to a financial audit).
- Competence requirements for verification bodies.
- The structure and content of the verification statement.
Verification under ISO 14064-3 is what transforms self-reported emissions data into independently confirmed data. This distinction matters when organizations submit their GHG inventory to regulators, investors, or trading partners who need confidence in the numbers.
ISO 14064 vs GHG Protocol: How Do They Relate?
One of the most common questions in corporate carbon accounting is whether ISO 14064 and GHG Protocol are alternatives or complements. They are complementary, not competing.
GHG Protocol’s Corporate Standard provides detailed, step-by-step calculation guidance: how to classify emissions into Scope 1, 2, and 3, which quantification methods to use, and how to handle challenges like base year recalculations or biogenic emissions.
ISO 14064-1 operates at a higher level. It defines principles and requirements the inventory must meet regardless of calculation methodology. It focuses on the management system: boundary definitions, documentation, internal controls, and preparation for independent verification.
In practice, organizations use GHG Protocol as the “how to calculate” reference and ISO 14064-1 as the “how to manage and verify” framework. The 2018 revision of ISO 14064-1 reduced friction between them by expanding indirect emission categories to mirror GHG Protocol’s Scope 3 structure.
Where ISO 14064 adds distinct value is in verification (Part 3). GHG Protocol does not include a verification standard. Organizations wanting independent assurance rely on ISO 14064-3. This is why a well-rounded carbon accounting program typically references both.
Why Does ISO 14064 Matter for Organizations?
Emissions data that cannot be verified is difficult to defend. As climate-related disclosure requirements expand across Europe and globally, the question is shifting from “do you measure emissions?” to “can you prove how you measured them?” ISO 14064 provides the framework for answering that second question.
Several forces are making this more urgent.
- Regulatory requirements are tightening. The EU’s Corporate Sustainability Reporting Directive (CSRD) expects emissions data produced through auditable processes. The EU Emissions Trading System (EU ETS) and the Carbon Border Adjustment Mechanism (CBAM) both depend on verified emissions data. Organizations subject to these frameworks benefit from structuring their GHG inventory to meet ISO 14064-1 and verifying under ISO 14064-3.
- Financial stakeholders are raising the bar. Banks and investors increasingly expect climate disclosures aligned with IFRS S2. These require emissions metrics that are consistent, comparable, and traceable. ISO 14064 provides the structural backbone.
- Supply chain pressure is growing. Large buyers are asking suppliers to provide verified emissions data as part of procurement. An ISO 14064-aligned, independently verified GHG inventory provides a credible answer.
The pattern is the same across all three: the value of emissions data depends on traceability and verifiability.
How Does ISO 14064 Verification Work?
Verification under ISO 14064-3 follows a structured process. An independent, accredited verification body reviews the organization’s GHG assertion: the formal claim about emissions (for example, “our Scope 1 and 2 emissions for fiscal year 2024 totaled X tonnes CO2e”).
The process typically moves through four stages. First, the verifier reviews documentation: GHG management plan, calculation methodology, boundary definitions, emission factor sources, and data collection procedures. Second, evidence testing follows, which may include sampling activity data, checking emission factor versions, reviewing unit conversions, and testing calculations for material categories. Third, the verifier evaluates materiality and flags errors, omissions, or misstatements. The organization can correct these before the final statement. Fourth, the verifier issues a statement communicating the level of assurance (limited or reasonable) and any qualifications.
The critical element is the audit trail. Verification goes faster when every number traces back to its source: which data was collected, which factor applied, which version, which assumptions, which corrections. Organizations managing their GHG inventory in disconnected spreadsheets often struggle with this traceability as the inventory grows.
This is where carbon accounting software becomes practical. A platform built for GHG accounting, such as Carbondeck, centralizes activity data, links each calculation to its emission factor source and version, logs methodology decisions, and maintains a revision history. This does not replace good process design, but it provides the data infrastructure that makes ISO 14064 verification significantly more efficient.
How to Start Aligning with ISO 14064
Implementing ISO 14064 does not require starting from zero. If your organization already calculates its carbon footprint using GHG Protocol, much of the foundational work is done. Alignment typically involves strengthening the management layer around the calculation.
Document Your Boundaries Explicitly
ISO 14064-1 expects clarity on which entities and operations are included, which consolidation approach is used (equity share, operational control, or financial control), and why.
Formalize Methodology Documentation
Record which calculation approaches, emission factors (including source, version, and year), and assumptions apply to each emission category. This is not a one-time exercise; it needs updating each reporting period.
Establish Internal Quality Controls
Define who reviews data inputs, how errors are flagged, and how changes between periods are tracked. The goal is a repeatable process that does not depend on one person’s knowledge.
Build the Audit Trail from the Start
Every data point should trace to its source. Every methodological choice should be recorded. Retrofitting traceability later costs far more than building it in from day one.
Consider Your Assurance Level
Limited assurance involves less evidence gathering and is a practical first step. Reasonable assurance requires more extensive testing and is increasingly expected for material emission categories.
The most common mistake is treating ISO 14064 as documentation to complete after the numbers are finalized. The standard works best when its principles are embedded into data collection and calculation from the start.
Frequently Asked Questions (FAQ)
ISO 14064 is a voluntary standard. However, many regulatory frameworks (EU ETS, CBAM, CSRD) require verified emissions data, and ISO 14064-3 is the most widely recognized framework for that verification. In practice, alignment becomes necessary when stakeholders or regulators require independently assured emissions reporting.
GHG Protocol provides detailed calculation methodology for corporate GHG inventories (how to classify and quantify emissions). ISO 14064 defines the management, reporting, and verification requirements that the inventory must meet. Most organizations use GHG Protocol for calculation and ISO 14064 for structure and assurance.
ISO 14064-1 is used to design and manage an organization-level GHG inventory. It specifies requirements for defining boundaries, classifying emissions, selecting quantification methods, and reporting results in a way that supports independent verification.
Timelines vary by organization size and complexity, but a typical verification engagement for a mid-sized organization takes four to eight weeks from document submission to final statement. Organizations with well-documented processes and centralized data tend to complete verification faster.
Yes. The 2018 revision of ISO 14064-1 expanded its treatment of indirect emissions beyond Scope 2, introducing categories that align closely with GHG Protocol’s Scope 3 framework. Organizations can include and verify Scope 3 emissions within an ISO 14064-1 inventory.
Sources
- ISO 14064-1:2018, International Organization for Standardization — ISO 14064-1:2018
- ISO 14064-2:2019, International Organization for Standardization — ISO 14064-2:2019
- ISO 14064-3:2019, International Organization for Standardization — ISO 14064-3:2019
- GHG Protocol Corporate Standard, World Resources Institute — Corporate Standard | GHG Protocol
- EU Corporate Sustainability Reporting Directive (CSRD), European Commission — Corporate sustainability reporting
- Carbon Border Adjustment Mechanism (CBAM), European Commission — Carbon Border Adjustment Mechanism
