Everything you need to know about carbon offsetting for your flights

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Flying produces substantial carbon pollution. And, if you fly frequently, flying likely accounts for the majority of your personal carbon emissions. Many of us aren't willing or able to significantly reduce our carbon emissions by flying significantly less, but one option is to offset the carbon emissions from your travel by purchasing carbon offsets.

Granted, some carbon offsets are better than others. Here's what you need to know about offsetting the carbon emissions from your flights, including some high-quality options for purchasing offsets.

CO2 basics

Airplanes emit various particles and gases, including carbon dioxide (CO₂), into the atmosphere. In this article, we focus on CO₂ because it makes up 65% of global greenhouse emissions.

CO₂ is one of several greenhouse gases that occur in the atmosphere. When functioning properly, greenhouse gases regulate the earth's temperature. According to the US Environmental Protection Agency (EPA), human activities are responsible for almost all of the increase in greenhouse gases in the atmosphere over the last 150 years. When excess greenhouse gas exists in the atmosphere, heat becomes trapped and the planet warms.

Estimating your carbon footprint

The EPA website has a Carbon Footprint Calculator that estimates your household's carbon footprint. Unfortunately, although this calculator is detailed, it only considers driving a personal car for transportation and ignores other forms of travel like flights.

There are many calculators that can be used to estimate the carbon emissions related to flights. Many are simplistic and give a rough estimate by considering your mileage flown. If you're looking for an estimate of carbon emissions based on miles flown, BlueSkyModel's air mile model provides a simple calculation.

Some calculators go a step farther and consider your class of service, since larger seats take up more space and hence account for a greater amount of fuel used per passenger. The most detailed calculator we've seen also considers your plane type, since some plane types are significantly more fuel-efficient than others. However, even this calculator is just an estimate — exact loads, cargo weights, taxi times, fuel expended and more would be necessary to make an exact calculation.

Reduce your emissions

The most effective way to reduce your CO₂ emissions is to reduce your fossil fuel consumption. This could mean having a teleconference instead of traveling for a meeting. If you do travel, you can reduce your footprint by taking vacations closer to home, flying nonstop when possible, taking a bus, train or fuel-efficient vehicle instead of a short-haul flight, booking a flight on a more fuel-efficient aircraft, flying economy class instead of business class or flying business class instead of a private jet.

Related: Why you might want to tour Europe by train, not plane

Carbon offsetting

Understandably, you may not be willing or able to reduce your travel significantly. And given the opportunity, most of us wouldn't forgo a chance to fly in Etihad's The Residence just because economy class or business class would have less of a carbon footprint. This is where carbon offsetting can come in.

Carbon offsetting involves spending money to make up for putting carbon into the atmosphere. The money you spend effectively offsets your carbon emissions by supporting projects that produce clean energy or reduce carbon emissions in other ways.

Critics of carbon offsetting say that spending to offset emissions merely allows polluters to feel better about their emissions and discourages working to reduce them. While there may be some truth to that, if you're going to fly, offsetting your carbon emissions by supporting the right projects is better than doing nothing.

Certified carbon offset organizations

If you decide to offset your carbon emissions, you'll quickly find many companies and organizations willing to take your money. Unfortunately, not all of these provide high-quality carbon offsets.

Some companies have entire teams that evaluate carbon offsetting projects to ensure that they are high-quality. As individual consumers, we usually don't have the resources, time or access to evaluate individual projects in detail. The next best option is to get suggestions from environmental organizations you trust or well-recognized organizations that list certified and verified carbon offsetting projects.

Three organizations that provide such listings are Gold Standard, Green-e and Climate Action Reserve. On each organization's website, the projects are sortable by location and offset type(s). You can learn more about the projects and decide which offset project or projects looks the best to you. Gold Standard makes it easy to donate to a particular project on their website, while Green-e and Climate Action Reserve refer you to individual projects.

Airline carbon offset programs

Most airlines have internal practices and plans to decrease their carbon footprint. But, as some passengers become increasingly concerned about the carbon emissions associated with their travel, some airlines have started offering customers the opportunity to get involved.

This section describes some carbon offsetting programs offered to customers by airlines. For each of these programs, participation by customers is completely voluntary and independent from the flight booking process.

Alaska Airlines

Alaska Airlines has partnered with Carbonfund.org to allow customers to offset part of the carbon footprint from their flights. Details aren't provided about the specific projects except that they are third-party validated projects that reduce carbon emissions in the US.

Alaska Airlines customers can calculate a suggested offset based on their route. To offset round-trip flights between JFK and SEA, a donation of $8.21 is recommended.

Delta

Delta became the first US carrier to launch a carbon offsetting program for customers, in 2007. Customers can support three of The Nature Conservancy's carbon offsetting projects. The Rio Bravo Climate Action Project protects forest lands threatened by conversion to agriculture, the Clinch Valley Conservation Forestry Program protects and manages 22,000 acres of working forestlands in southwestern Virginia and the Valdivian Coastal Reserve supports traditional land use and forest restoration on Chile's southern coastline.

To offset round-trip flights between JFK and LAX, a donation of $10.33 is recommended. Delta also provides the ability to donate miles to The Nature Conservancy, but doesn't suggest a particular number of miles to offset specific flights.

JetBlue

JetBlue says it is proud to have offset more than 2 billion pounds of CO₂ since 2008. JetBlue has partnered with Carbonfund.org; the carbon offsets purchased by JetBlue and its customers help fund technology and forestry projects.

JetBlue customers can calculate a suggested donation to offset specific flight itineraries. To offset round-trip flights between JFK and LAX, the calculator recommends a $8.40 donation.

United

United's Eco-Skies CarbonChoice program partners with Conservation International to allow passengers to donate toward carbon reduction projects. One of the projects is the Alto Mayo Forest Carbon Project, which is a community-based forest conservation in Peru that is registered under the Verified Carbon Standard.

United's calculator estimates the carbon footprint of flying specific routes, although you can also simply choose to offset a set number of flight miles. To offset round-trip flights between New York (EWR) and Los Angeles (LAX), you could donate $7.48 to offset the 0.75 tons of carbon dioxide allocated to your economy seat on those flights.

Air Canada

Air Canada partners with Less Emissions to give customers the opportunity to purchase carbon offsets to reduce the environmental impact of their flights. No details are provided about the projects that are supported, but Less Emissions notes that the projects are chosen from Gold Standard-Certified International Offsets and VER+ Standard-Certified Canadian Offsets.

The Air Canada calculator estimates that round-trip flights between JFK and Vancouver (YVR) create 0.760 tons of carbon emissions per passenger. It costs CAD 32 ($24) per metric ton to purchase Gold Standard-Certified International Offsets and CAD 24 ($18) per metric ton to purchase VER+ Standard-Certified Canadian Offsets. So, based on their calculator, it costs CAD 24.33 ($18) to use international offsets or CAD 18.25 ($14) to use Canadian offsets to carbon offset these flights.

Air New Zealand

Air New Zealand partners with ClimateCare to support two types of projects: (1) native forest restoration projects in New Zealand that reward landowners for permanently preserving forests and (2) international projects chosen to create community as well as climate benefits.

The Air New Zealand calculator estimates that round-trip flights between JFK and Auckland (AKL) create 2,081 kilograms of carbon emissions per passenger. Based on their calculator, it costs NZD 47.18 ($30) to carbon offset these flights.

Austrian

Austrian Airlines partners with Climate Austria to support three types of projects: renewable energy projects in Austria, efficient cooking stove projects in Kenya and forest conservation in the Democratic Republic of the Congo.

The Climate Austria calculator estimates that round-trip flights between JFK and Vienna (VIE) create 1.427 tons of carbon emissions per passenger. Based on their calculator, it costs €35.68 ($39) to carbon offset these flights.

Brussels Airlines

Brussels Airlines partners with CO2logic to support two projects: efficient cook stoves in Uganda and water treatment in Kenya. Both projects are certified by the United Nations and/or Gold Standard.

CO2logic's Greentripper calculator considers the class of service when calculating carbon offsets. For round-trip flights between JFK and Brussels (BRU), an estimated 1.42 metric tons of carbon emissions are allocated to each economy seat, 3.08 metric tons are allocated to each business seat and 4.66 metric tons are allocated to each first class seat. The Greentripper calculator estimates that each metric ton takes €12.10 ($13) to offset, so an economy class seat on this route would cost €17.18 ($19) to offset.

Cathay Pacific

Cathay Pacific's FLY greener program was launched in 2007 and supports two projects that are verified according to The Gold Standard. The first project focuses on converting food waste into clean energy via biogas digesters in India while the second project supports efficient cook stoves in Bangladesh.

For round-trip flights between JFK and Hong Kong (HKG), Cathay Pacific's carbon emissions calculator allocates 2.24 metric tons of carbon emissions per economy seat, 2.8 metric tons per premium economy seat, 3.36 metric tons per business class seat and 4.48 metric tons per first class seat. The carbon offset price is set at HKD 19.27 ($2) per metric ton or 475 Asia Miles per metric ton, so an economy class seat can be offset for HKD 43.17 ($6) or 1,064 Asia Miles. This values Asia Miles at 0.52 cents while TPG's latest valuation values Asia Miles at 1.3 cents.

China Airlines

China Airlines has partnered with ClimateCare to support environmentally friendly and sustainable carbon reduction projects, although details aren't provided about the specific projects. The China Airlines calculator considers your class of service. For round-trip flights between JFK and Taipei (TPE), a seat in economy is allocated 1.88 metric tons of carbon emissions and a seat in business/upper is allocated 3.76 metric tons. The 1.88 metric tons allocated to an economy seat can be offset by a $19.48 donation.

EVA Air

EVA Air has also partnered with ClimateCare to support various projects that reduce carbon emissions, although no details are given regarding the specific projects. The EVA Air calculator considers your class of service. For round-trip flights between JFK and Taipei (TPE), a seat in economy is allocated 1.5 metric tons of carbon emissions and a seat in business/upper is allocated 3.01 metric tons. The 1.5 metric tons allocated to a business/upper seat can be offset by a $15.55 donation.

Japan Airlines (JAL)

Japan Airlines directs passengers to myclimate if they wish to offset their flights. The myclimate calculator considers your route and class of service. For round-trip flights between LAX and Tokyo Narita (NRT), a seat in economy is allocated 2.9 tons of carbon emissions, a seat in business is allocated 5.5 tons and a seat in first is allocated 8.5 tons. The 2.9 tons allocated to an economy class seat can be offset by a $78 donation to international projects and sustainable development worldwide, or you can donate a larger sum of money toward a specific region or project.

Lufthansa

Lufthansa partners with Myclimate to support a couple projects: energy from wood waste in Brazil, clean biogas in Indonesia and energy-efficient cook stoves in Madagascar and Kenya. All four projects are registered under The Gold Standard.

Myclimate's calculator for Lufthansa allocates different carbon emissions to passengers in economy, premium economy, business and first. For round-trip flights between JFK and Frankfurt (FRA), Myclimate's calculator allocates 0.758 tons of carbon emissions to economy passengers, 1.1 tons to premium economy passengers, 1.6 tons to business class passengers and 2.4 tons to first class passengers. It costs $17 to offset the 0.758 tons of emissions allocated to an economy class seat.

Qantas

Since 2007, Qantas and its customers have offset over 3 million tons of carbon emissions through Qantas Future Planet, which it claims makes it the largest offsetter of any airline.

There are three offset projects featured on the Qantas Future Planet website. Reinvigorating Indigenous Traditions uses traditional fire management techniques to reduce emissions in North Kimberley. Empowering Rainforest Communities supports the April Salumei project in Papua New Guinea. And, Conserving Tasmania’s Wilderness protects over 7,000 hectares of native Tasmanian forest from selective logging or conversion to pasture. All three projects meet strict international standards.

To offset a round-trip flight between LAX and Sydney (SYD) a donation of AUD 37.13 ($25) is recommended.

Comparing airline programs

Each airline program described in this article supports different projects that have different costs for carbon offsetting. The table below compares the projects. For simplicity, the route examples from this article are used to calculate the average rate to carbon offset 1,000 miles for each program.

After researching how to donate to carbon offsetting projects, I was surprised by the high quality and standards of many of the projects supported by airlines and their customers. Perhaps I shouldn't be surprised though: airlines have the resources to find high-quality partner organizations which in turn have the resources to find and vet high-quality projects.

All of the airlines shown in the table above and discussed in this article offer the ability to carbon offset flights independent of a specific booking. Some airlines, including British Airways, JetStar, Thai Airways and Virgin Australia, only offer the ability to add a carbon offset donation during booking or for a specific reservation.

Carbon offsetting in practice

So, you're likely wondering how much carbon offsetting would really cost you in practice. Let's consider a few examples based on a recent TPG mileage run competition, as well as on my own travel.

Samantha Rosen flew 21,665 miles for that mileage run competition. According to BlueSkyModel's air mile model, this mileage run created an estimated 2.36 metric tons of carbon emissions. TPG offset Samantha's flights by purchasing carbon offsets on the Gold Standard website that would offset a range of Gold Standard certified projects at a cost of $11 per metric ton. Gold Standard only sells offsets by the metric ton, so we purchased $33 of offsets using the Chase Ink Business Preferred Credit Card. The purchase coded as Gifts and donations, so we only earned 1 point per dollar spent.

Victoria Walker flew 20,419 miles on her run, purchased on United Airlines, creating an estimated 3.04 metric tons of carbon emissions according to United's calculator. TPG offset her flights by purchasing $30.38 of carbon offsets though United's partnership with Conservation International, using the Chase Sapphire Reserve card. The purchase coded as Gifts and donations, so we only earned 1 point per dollar spent.

The third mileage run contestant, Zach Wichter, flew 21,214 miles on his run, purchased through Delta, which created an estimated 3.84 metric tons of carbon emissions according to Delta's calculator (which calculated his route as a slightly shorter 21,162 miles). TPG offset his flights by purchasing $57.54 of carbon offsets though Delta's partnership with The Nature Conservancy. We used the Citi Premier® Card, which coded the purchase as Charitable/Social Service Organizations so it only earned 1 point per dollar spent.

Now, let's consider how much it cost to offset one of the Cathay round-trip flights I booked as part of Cathay's New Year's deal, in business class between Da Nang, Vietnam, and Hong Kong and first class between HKG and New York JFK. My seat on these flights was allocated about 4.73 metric tons of carbon emissions, which Cathay's calculator estimates could be offset by a HKD 91.15 ($12) donation.

I was allocated more emissions than any of the mileage runners, even though my route was only 17,284 miles, since first and business class seats take up more space on the aircraft. But, I paid much less than they did for carbon offsets for these flights because Cathay charges less for offsets than most other programs. I purchased the offsets using The Platinum Card® from American Express, which coded the purchase as Airfare so I earned 5 points per dollar spent on the donation.

As you can see from these examples, different models calculate different estimates of carbon emissions due to assumptions made by each model. And, different carbon offset organizations charge different amounts to offset a metric ton of carbon emissions because some projects are likely more expensive than others.

But, what if you wanted to offset all of your flights for a year? OpenFlights shows that I flew 236,601 miles in 2018 and BlueSkyModel's air mile model estimates that one passenger seat on these flights produced 25.76 metric tons of carbon emissions. A wind power project on the Gold Standard website charges $10 to offset each metric ton of CO₂, so at this rate it cost $260 to offset the flights I took in 2018. I purchased $260 of offsets using my Capital One Venture Rewards Credit Card, which earned 2 miles per dollar spent (for those looking to use other cards, the transaction posted as Other).

Whether you're booking a flight or making a donation, make sure you're using a credit card with no foreign transaction fees if there's a chance the charge may be processed outside the U.S. And, since most donations tend to code as charity, you may want to use a card with solid earnings on charity spending or just use the safe bet of picking the best card in your wallet for everyday spending. However, as I saw with my donation through Cathay Pacific, some donations through airline programs may code as airfare.

Bottom line

Before research carbon offsetting, I had many qualms about how my money would be used. And I wasn't sure which projects would provide the best carbon offsets. I easily found many projects and organizations that were ready to take my money -- but many of these projects and organizations had little evidence of verification or certification and didn't provide adequate information about how they'd offset carbon emissions.

But there are also high-quality projects and organizations. In particular, I was surprised by the high quality and standards of many of the projects supported by airlines and their customers.

If you want to offset your carbon emissions, make sure to find a high-quality project that's certified and verified. And, if you currently give to a carbon offsetting project that you're passionate about, let us know below.