Carbon Offsets: Frequently Asked Questions

Why it is important for travelers and tourism businesses to purchase offsets?

Greenhouse gases (GHG), like carbon dioxide (CO2), are emitted when fossil-fuels are consumed. We all emit CO2 emissions when we drive a car, fly in a plane, use electricity, or generate waste. You can use less energy, travel less, or use public transport, but no matter how sustainable your practices are, some emissions are unavoidable.

Tourism is responsible for roughly 8% of the world’s carbon emissions, making it a significant contributor to global climate change. Travelers and tourism businesses should take responsibility for this impact by offsetting their carbon footprint so that the destinations they frequent and depend on will be there for them to visit again in the future.

What is carbon offsetting?

Carbon offsetting is the act of reducing carbon dioxide or greenhouse gases in order to compensate for emissions that were produced elsewhere. Travelers are able to ‘offset’ the carbon emissions produced from their plane flights, ground transportation and other activities by purchasing carbon credits. One carbon offset credits represent 1 metric ton of CO2e reduced or averted from the atmosphere. The funds from these carbon credit sales are distributed to certified emission reduction projects around the world, making the continuation of their activities economically feasible.

How do you calculate my carbon footprint?

The amount of carbon emissions that a traveler generates varies depending on the type of transportation used (flight, car, boat), engine burn rate, distance traveled, etc.

Our online carbon footprint calculator utilizes average CO2 emissions factors of air travel, passenger vehicles, and fuel consumption provided by the DEFRA statistical analysis database.

In the case of air travel, a passenger will emit 0.14 to 0.55 kg Co2e per passenger kilometer depending on the class and flight distance. Therefore, for every 10,000 passenger kilometers, this is approximately 0.14 to 5.5 Metric Tons (MT) of Co2e per passenger.  For specific flight itineraries, our calculator automatically calculates the distance utilizing the shortest route in nautical miles between the departure and arrival airports.

In the case of passenger vehicles, emissions will vary from 0.11 to 0.20 kg Co2e per kilometer driven or 0.17 to 0.33 kg Co2e per miles driven depending on the type of vehicle.  Therefore, for every 10,000 kilometers driven a passenger vehicle will emit 1.1 to 2 MT of Co2e, likewise for every 10,000 miles driven a passenger vehicle will emit 1.7 to 3.3 MT of Co2e.  An estimated 45mph/72kmh is used to convert hours to distance traveled. 

To calculate charter plane C02 emissions, our online calculator utilizes Paramount Business Jets’ open-source private jet carbon emissions methodology.  The emissions of charter flights depends on the flight time, the fuel burn rate, and C02 coefficient for Jet Fuel (22.1 lbs of C02 emitted per gallon of fuel burnt); as specified by the US Energy Information Administration.  The fuel burn rate of charter planes can vary from 48 to 907 gallons per hour depending on the type of plane.  A private jet will emit approximately 2,026 to 38,275 lbs of C02e per hour equivalent to 0.5 to 8.7 MT of C02e per hour.

For private yacht and boat travel, the CO2 emissions factor ranges from 0.6 to 2.5 Kg of Co2e per liter or 2.28 to 9.6 Kg of Co2e per gallon of fuel. For every 10,000 liters of fuel consumed, 6 to 25 MT of Co2e is emitted. Likewise for every 10,000 gallons of fuel consumed 23 to 96 MT of Co2e is emitted.

The liveaboard and cruise CO2 emissions factors are derived based on benchmarks as well as Sustainable Travel International’s undisclosed carbon footprint reporting from clients who operate large cruises to small liveaboard operations.  The amount of carbon emissions generated per passenger varies from 293 to 561 Kg of Co2e per day or 0.3 to 5.6 MT of Co2e per day. 

Where do my offset dollars go?

When you purchase carbon offsets from Sustainable Travel International, we will offset the amount of carbon dioxide you indicated by distributing your investment across our mixed portfolio of forestry, energy, and blue carbon projects. These projects either remove existing carbon emissions from the atmosphere or prevent new emissions from happening. View our Carbon Offset Project Portfolio here to see the most recent allocation of our portfolio, as well as a selection of past projects that have been supported.

To maximize the impact of your contribution, we handpick every project that we include in our portfolio, ensuring they comply not only with the most rigorous international standards for carbon offsetting but also pass our own due diligence process. In addition to fighting climate change, we seek out projects that deliver social and environmental benefits beyond CO2 reductions and contribute to the UN Sustainable Development Goals by creating transformative benefits like improved hygiene and health services, new jobs, increased food security, education, and flourishing wildlife habitats.

If you have a large amount of carbon to offset and are looking to invest in projects which provide particular benefits or are located in a specific geographical area, you may be able select which project(s) you would like to support. Please contact us directly to explore your options.

How can I ensure the integrity of my investment?

A cause-focused organization

By offsetting through Sustainable Travel International, you can be sure that your dollars are being used to make a difference for our planet and protect the destinations you care about. Since we’re focused on holistic sustainability, the portion of your investment that stays with us supports our wider mission of protecting and conserving destinations around the globe.

Third-party certification

All of the projects in Sustainable Travel International’s portfolio have been verified and/or certified by an independent third-party organization to comply with at least one stringent carbon offsetting standard. The on-going performance of each project is monitored by the evaluation agencies and their local partners at least once a year throughout the verified life cycle of each project.


It is important to note that we don’t consider all renewable energy or reforestation projects as eligible carbon offset projects. We only support projects that adhere to the concept of “additionality,” which means that the emission reduction intervention creates an additional environmental benefit than would not have occurred otherwise. In other words, the intervention would not have occurred if not for the financial support from carbon offsetting. The number of carbon credits issued for a project (that are then made available for trade) must equal the amount of annual carbon emission reductions that result from the project. Third party certification bodies are responsible for validating the emission reduction methodology and verifying that they are following their project plan and creating real impacts.


Whether it be through natural causes or human involvement, if ecosystems are damaged or destroyed, the carbon that was stored during the project may be released into the atmosphere.  This would undo all the effort made by everyone involved in the project. To maintain the longevity and “permanence” of carbon sinks and ensure that they do not become a future source of CO2, third-party certifiers conduct stringent investigations before validating a project.


When the creation of a project that aims to reduce greenhouse gases (GHG) unintentionally increases GHG emissions somewhere else, this is called “leakage”.  For example, if trees are planted on an area of agricultural land, or logging activity is prohibited in a certain area, this may shift the problem of deforestation elsewhere.  There are strict protocols in place to avoid this, helping to ensure the integrity of carbon offsetting investments.


Our projects are listed on public registries and when a carbon offset is sold it is then ‘retired’.  This renders the credit as used and ensures that it is not sold twice. This reduces the possibility of carbon offset credits being double-counted. We retire your carbon credits once we sell a threshold of 5,000 MT tons or within one year of purchase – whichever comes sooner. 

What are the Sustainable Development Goals (SDGS)?

We carefully select which carbon reduction projects we support based on the co-benefits they provide to local communities and biodiversity. The UN’s 17 Sustainable Development Goals (SDGs) goals aim to address global inequalities and challenges by the target date of 2030, while aiding development and protecting the environment. We ensure that our projects align with as many of these SDGs as possible, to ensure that the impact of your offset purchase goes far beyond carbon reduction.

What’s the difference between the voluntary carbon market and the compliance carbon market?

The voluntary carbon market is driven by companies and individuals taking responsibility for their own emissions by choosing to offset their carbon.  The voluntary market can be more flexible and innovative than the compliance market and allows many communities and ecosystems to benefit from offsetting.  When you purchase carbon offsets from Sustainable Travel International, you are investing in the voluntary offset market. This marketplace offers us an opportunity to reduce greenhouse gas emissions while addressing development needs of certain countries. 

Compliance carbon markets allow entities to obtain and surrender emissions permits or offsets in order to meet international and national regulatory targets. These are usually enforced by law and come in the form of cap-and-trade programs where participants trade carbon allowances (credits) in order to make a profit from unused allowances or to meet regulatory requirements. 

The main difference between the compliance and voluntary markets is the fact that a voluntary carbon credit cannot be used by entities to meet their obligations under a regulatory scheme. This means there is no steady stream of income reaching our voluntary projects so your investments can have a huge impact on the communities and ecosystems we support.

Is my carbon offset purchase tax-deductible?

No. Purchasing carbon offsets is not a donation but a purchase. As such, it is not tax deductible. A great analogy is how the Girl Scouts sell Girl Scout Cookies. When we buy those cookies it’s a purchase not a donation. Like the Girl Scouts, Sustainable Travel International does accept donations via its fiscal sponsor, the Ocean Foundation, to support its work on sustaining destinations and preserving landscapes. Those donations are tax deductible.

Climate Change Glossary

Look up definitions of key terms related to climate change, carbon emissions and offsets, and climate action in our Climate Change Glossary.

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