Frequently Asked Questions

What is carbon offsetting?

Carbon offsetting allows individuals and businesses to reduce their environmental impact. By purchasing independently verified carbon offsets, customers support environmental projects that remove greenhouse gas emissions from the atmosphere (such as planting trees) or prevent future emissions from occurring (such as replacing a coal-fired power station with a wind farm). One unit of carbon offset represents one metric tonne of greenhouse gas emissions avoided or removed from the atmosphere.

Why do we only refer to carbon?

There are seven main greenhouse gases: carbon dioxide, methane, nitrous oxide, chlorofluorocarbon, hydrofluorocarbon, sulphur hexafluoride, and nitrogen trifluoride. Each greenhouse gas has a different environmental impact which can be measured through the Global Warming Potential (GWP) metric. Based on their respective GWP, each greenhouse gas can be converted into carbon dioxide equivalent (CO2e) to determine their individual and combined contributions to global warming. Hence, carbon offsetting is typically transacted in CO2e as a common unit.

How does carbon offsetting work for flights?

Emissions from each Singapore Airlines (SIA) flight are calculated on a per-passenger basis. When you choose to offset your share of emissions from your flight, the equivalent number of carbon offsets purchased will be retired by TEM.

How are my flight emissions calculated?

The flight emissions are computed using TEM BlueHalo® technology. The BlueHalo® software uses the current UK Department for Environment, Food and Rural Affairs (DEFRA) international standards to convert greenhouse gas emissions associated with your flight such as aircraft type, distance travelled, and litres of fuel used, to tonnes of CO2e. The BlueHalo® calculations are continually updated as best practice international standards for greenhouse gas calculations evolve.

I am connecting to/from another airline. Can I offset my carbon footprint from a partner airline’s flight via SIA’s voluntary carbon offset programme?

The SIA Group voluntary carbon offset programme was introduced for SIA or Scoot operated flights only.

Is the carbon footprint different for different cabin classes?

Yes. The seats in each cabin class take up a different amount of space and weight on the aircraft. As different cabin classes have a different impact, we have factored this into our calculations in accordance with international standards.

How do you know that the offset is really happening?

The SIA Group supports carbon offset projects that are verified in accordance with international standards by independent third-party auditors under the Verified Carbon Standard Program and the Gold Standard. These standards ensure that each project delivers real, measurable emissions reductions, which would not have occurred in a business-as-usual scenario where the project would not have been implemented. Each project is then issued carbon offsets, and each offset holds a unique serial number for traceability to prevent double accounting in the market. For instance, if the project demonstrated a reduction in 1,000 tonnes of emissions, they would be issued with 1,000 verified carbon offsets. Supported projects are also compliant or finalising compliance with strict criteria under the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA), which is governed by the International Civil Aviation Organization (ICAO). Carbon offsets purchased by customers are retired by TEM in the respective carbon registries where the projects are verified. This ensures that the offsets cannot be traded again.

Which offset projects does my contribution support?

The SIA Group supports a portfolio of accredited projects, which brings about environmental and socio-economic benefits to communities in Asia. These projects include:

  • Forest restoration initiatives in Indonesia which capture and store carbon in trees, preserve habitats for native wildlife, and support the development of local villagers through employment and training opportunities.
  • Solar energy projects in India that generate clean renewable electricity for power, which would otherwise have been supplied by a fossil-fuel fired power plant. These projects also create jobs, and strengthen rural electrification coverage.
  • Distribution of efficient, clean burning cookstoves, which significantly reduce the amount of smoke produced during cooking and associated health risks, particularly for women and children who are responsible for preparing meals in Nepal.

Learn more about the projects we support here.

What is the conversion rate if I use my KrisFlyer miles to pay for my carbon offset?

The rate is 150 KrisFlyer miles for every S$1 worth of carbon offset.

I do not have enough KrisFlyer miles, but I would like to support this Carbon Offset Programme. Can I purchase miles to pay for my carbon offset?

No, you cannot purchase miles to pay for your carbon offset. If there are insufficient miles in your KrisFlyer account, you can consider paying for carbon offsets via debit or credit card in full, or for selected flight segments.

Do I get a refund if I cancel my booking?

To purchase a carbon offset is to make a contribution to a verified carbon project. Hence, if a customer pays for an offset but does not travel, no refund will be accorded.

Can I offset my flight when I book my flight?

Customers are encouraged to offset their flight emissions through our dedicated microsite at We are committed to providing a seamless carbon offset experience and will continue to review and enhance our processes.

Does SIA profit from this programme?

No. SIA does not profit from the sale of carbon offsets purchased under the carbon offset programme. All contributions made by customers are used to source carbon offsets from projects worldwide, which include administration fees paid to TEM to carry out due diligence of sourcing and supplying carbon offsets, including managing the offset retirement process and all carbon accounting.

What else is SIA doing to reduce its environmental impact?

The SIA Group continues to find new pathways to reduce our impact on the environment. At the same time, we remain committed to enhancing our customers’ journeys with us. Learn more about our sustainability initiatives here.

Can I offset my company’s flight emissions?

Since December 2021, the SIA Group’s Carbon Offset Programme for businesses has been made available for SIA’s corporate customers. They may calculate and offset the carbon emissions emitted from their companies’ business travel via this website . From 23 April 2023, corporate customers can also pay for carbon offsets using their HighFlyer points. Corporate customers who are keen to find out more can reach out to their account managers.

Does SIA participate in CORSIA?

Developed by the International Civil Aviation Organization (ICAO) in 2016, the Carbon Offsetting and Reduction Scheme for International Aviation (CORSIA) is a programme to lower carbon emissions for international flights and reduce aviation’s impact on climate change. It is the first global market-based measure developed for the aviation sector to offset residual carbon emissions that cannot be directly reduced through technological and operational improvements, and sustainable aviation fuels, in order to meet ICAO’s aspirational goal of carbon neutral growth from 2020. ICAO sets strict criteria for which carbon offset project development programmes are eligible for compliance under CORSIA. CORSIA plays an integral role in helping the aviation industry decarbonise in a cost- efficient manner. The SIA Group has voluntarily participated in it since 2019, ahead of the mandatory implementation for all airlines from 2027.

Why does SIA offer offsetting when it complies with CORSIA?

While SIA supports and complies with longer-term international obligations under CORSIA to reduce emissions from international aviation, we believe that every act counts and we aim to empower our customers to play a part in reducing their impact on the environment and contribute back to society. Voluntary contributions to the programme help to bring about environmental and socio-economic benefits to communities in Asia.

Is my contribution helping SIA reach its CORSIA obligations?

No. SIA will manage all compliance requirements under CORSIA at our own cost.

Who is TEM?

TEM, is an Australia-registered carbon offset service provider that supports the SIA Group Voluntary Carbon Offset Programme through its BlueHalo® digital platform which allows instant calculation of customers’ flight emissions and the offset of those emissions via this website.