What error margin does a Verra verifier allow in our reported reductions?

Five percent, or one percent for large projects. Under VCS Standard v5.0 a VVB verifies to reasonable assurance, and errors, omissions and misrepresentations taken together must stay below 5% of the total reductions or removals you report. Projects above 300,000 t CO2e a year face the 1% threshold.

Which threshold applies to you

• Project: up to 300,000 t CO2e a year on average. Threshold 5%.
• Large project: more than 300,000 t CO2e a year. Threshold 1%.
• The threshold applies to the aggregate of errors, omissions and misrepresentations, measured against the total reported in that verification.

When the VVB comes to site

• Always at validation and at each crediting period renewal.
• At the first verification after validation, at verifications that include a baseline reassessment, and when a project description deviation affects methodology applicability, additionality or the baseline.
• Otherwise the VVB decides from its own risk assessment and must document why if it skips the visit.
• If the visit falls before the monitoring period ends, the VVB still has to verify the tonnes generated after it.

Where small errors usually come from

• Meter readings typed into a spreadsheet by hand.
• Months with missing fuel or electricity bills filled in by estimate.
• Unit mix-ups, such as kVAh read as kWh or litres as kilograms.
• Default factors used where the methodology asks for measured values.

Example: a monitoring report claiming 40,000 t CO2e

• Materiality threshold: 40,000 x 5% = 2,000 t
• Errors found: transcription error 1,200 t plus two estimated months 500 t = 1,700 t overstated, below the line
• One more 600 t error: 2,300 t, above the line, so the report must be corrected before a positive opinion
• A large project claiming 400,000 t would have a threshold of 400,000 x 1% = 4,000 t

All errors here overstate. Ask your VVB how it treats errors that point in opposite directions.

What Senseible does here

Senseible checks each figure against its source document and flags a quantity, unit or factor that does not match, before a VVB samples it. Its Verified status means those rule checks passed; the VVB's opinion is separate and independent.

• What materiality means in verification
• Acceptable error in a carbon audit
• Verra VVB rotation
• Carbon credits

Sources: Verra, VCS Standard v5.0 (16 December 2025): Sections 3.9 and 4.1.9 to 4.1.13

Last reviewed 2026-11-03. Thresholds and site visit triggers are in section 4.1 of the current VCS Standard; recheck on a new version.