How much of my carbon credits go into the buffer pool, and why?
Under Verra, a land-based project puts a share of each verification's carbon stock gain into a shared buffer pool, equal to its non-permanence risk rating; a project rated above 60 percent fails. The buffer exists because trees, soil and mangroves can lose stored carbon later, through fire, drought or land clearing.
What the buffer pool is for
A tonne avoided at a chimney stays avoided. A tonne stored in a tree or in soil can go back to the air. Registries handle that risk by holding back part of every land project's credits in a common pool that no one can sell. When any project in the pool loses carbon, the registry cancels buffer credits to cover the loss, so the credits buyers already retired stay whole.
It works like pooled insurance: every project pays a premium in credits, and the pool pays out for the ones that suffer a loss.
What sets your share
- Internal risk: how sound the project's management and finances are, how long the project commits to, and whether the landholders have a reason to keep the carbon in place.
- External risk: land tenure and use rights, community engagement and political risk in the region.
- Natural risk: fire, flood, drought, pests and storms, judged by how likely and how severe they are at your site.
- Verra's AFOLU Non-Permanence Risk Tool adds these scores into one rating, which becomes the percentage withheld. The rating cannot go below a floor the tool sets, and a project rated above 60 fails the analysis and cannot issue until it reduces its risks. Take the floor from the current tool version, as Verra has revised it.
What the Indian project types tend to face
Agroforestry on smallholder farms often scores higher on internal and external risk, because thousands of farmers each control their own trees and can cut them. Soil carbon projects depend on farmers keeping the practice going after payments end. Coastal mangrove projects carry cyclone and tidal surge risk on the natural side. Clear farmer agreements, documented land rights and fire or grazing controls are what bring a rating down.
What happens when carbon is lost
- You report a loss event to the registry within the time its rules set.
- Buffer credits equal to the lost tonnes are cancelled, so credits already sold stay whole.
- Whether new issuance from your project pauses until the loss is made up is set by the current VCS Standard; check it before you plan around a loss.
- If the loss was avoidable, for example the land was cleared on purpose, the rules put more of the burden on the project rather than the shared pool.
Other programmes handle it differently
Gold Standard land-use projects hold back a fixed 20 percent rather than a project-specific rating, and that pool is kept even after the crediting period ends. ICVCM's Core Carbon Principles treat permanence as one of the tests a credit type must pass, so a programme needs some reversal protection, such as a buffer, before its land credits can carry the CCP label.
Illustrative: one verification of an agroforestry project
- Net carbon stock gain verified for the period: 10,000 t CO2e
- Risk rating: 15% (illustrative; yours comes from the tool)
- Buffer credits: 10,000 x 0.15 = 1,500
- Credits issued to you: 10,000 minus 1,500 = 8,500
- Under a fixed 20% buffer instead: 2,000 to the pool and 8,000 issued
The rating multiplies only the carbon stock change. Reductions that cannot reverse, such as avoided methane, follow your methodology's own rule. Plan revenue and forward sales on issued credits, not verified tonnes.
What Senseible does here
Senseible does not calculate risk ratings, run a registry or hold buffer credits. Its carbon credit eligibility signals show whether your records look ready for a methodology; they are not credits and not a non-permanence assessment.
Sources: Verra, VCS AFOLU Non-Permanence Risk Tool and VCS Standard (buffer and reversal rules), Gold Standard, Land Use and Forests requirements (reversal buffer), ICVCM, Core Carbon Principles (permanence)
Last reviewed 2026-10-16. Verra revises the Non-Permanence Risk Tool; check the current version for the minimum rating and reversal rules. The above-60 fail line and the Gold Standard 20 percent buffer were checked in October 2026; the 15 percent rating is illustrative.