Offset Providers
Helps companies to create sustainability plans.
Offsets help to build American Indian-owned renewable energy projects.
Offsets support projects to reduce methane and nitrous oxide in agriculture.
Offsets support collecting landfill gas from a facility outside Chicago and using it as fuel for generating electricity.
Offsets support projects in developing countries.
Read the CarbonNeutral Protocol, an exhaustive guide to evaluating projects.
Choose from renewable energy, energy-efficiency, and reforestations projects.
Offsets support low carbon technologies in developing countries.
Read project case studies.
Wide variety of projects
Offshoot of The Conservation Fund; focus on reforestation
In addition to earning certifications such as the CDM Gold Standard, projects meet internal standards for respecting local culture and generating positive side benefits for the community.

Standards & Certifications
Clean Air-Cool Planet commissioned the first report vetting 30 carbon-offset providers. Because the marketplace of offset providers has expanded since the research was done, CA-CP considers the specific vendor assessments in the report outdated. Still relevant and available, however, is CA-CP's comprehensive review methodology, which companies could use to assess their own potential vendors.
A Web site created by the Environmental Defense Fund. Recommends four providers selling offsets for $4 to $8 per ton of CO2.
The Gold Standard certification, developed by several international nonprofit organizations, is given only to renewable energy and energy efficiency projects — in other words, those that seek to reduce emissions in the first place.
Certifies renewable energy credits. A word of warning: Some organizations consider RECs, which are most often used to buy wind power and “add it to the grid,” problematic. That's because of the challenge of meeting the “additionality” test — the test of whether this renewable energy would have been produced anyway, in the absence of the RECs.
This nonprofit offers the Greenhouse Gas Protocol Corporate Standard, which helps companies to prepare a GHG inventory that represents a true account of their emissions.

Get the Lowdown

Sustainable Travel International ( estimates that offsetting the carbon emissions of an event can cost $250 to $2,000, depending on the event's size. Including offsets for attendee hotel stays and air travel adds $25 to $50 per person.

But questions arise. Who calculates your footprint? Who sells you the offsets? Who verifies that your money goes to a viable project? What about “double counting”? (That is, are you being sold the same offsets that someone else is buying?)

Experts recommend that, because the industry is not yet regulated, you start with an organization that certifies or vets carbon providers, or rely on references from other planners who have already done the screening.