Cleared for landing: airports are the latest unexpected issuers of sustainable bonds
Aeroporti di Roma has become the latest to join the ranks of airport SLB issuers but as issuances from airport operators increase, investor demand for accountability will rise too
It seems unlikely that airports have much to do with green debt. After all, the agenda for decarbonising aviation is largely steered by airlines, alternative fuel suppliers and regulators. Yet if aviation is to be reimagined, so too must its infrastructural backbone.
Airport infrastructure – an overlooked piece of the puzzle – is built, managed and financed by airport operators. Green debt issuance from the sector is on the rise.
The latest comes from Aeroporti di Roma (ADR) – which manages Rome’s Fiumicino and Ciampino airports. Last week, ADR issued its fourth SLB and reported strong demand from ‘ESG specialised investors’. The €500m issuance was three times oversubscribed.
Net Zero Investor’s Sustainable Bonds Summit
4th March 2026. Central Court, London
Rising popularity
Airport operators are no strangers to green debt. Issuances have risen in recent years.
London Heathrow has four SLBs outstanding. London Gatwick has two. Amsterdam’s Schiphol airport has hitherto issued $2bn in green debt. Korea’s Incheon airport has raised $300mn. Hong Kong airport is the second largest issuer in the category, and Mexico City airport was an early pioneer – having issued its first bond a decade ago.
That is according to data from the Anthropocene Fixed Income Institute (AFII), which has been tracking labelled debt issuance from airport operators.
“We have been seeing SLB issuance from airports for a while”, says Jonas David, research director at AFII.
“Airports are often in focus due to their critical role in facilitating air travel (and related emissions), SLB structures can help strengthen the credibility of decarbonisation ambitions due to explicit targets”, he explains.
Low hanging fruit
For airports, green debt instruments call into question their emissions reduction plans.
Decarbonising their own operational emissions – scope 1 and 2 – is relatively low hanging fruit. Examples of airports investing in renewable energy supply are becoming increasingly common.
India’s Cochin International airport is powered entirely by solar energy. Edinburgh airport has an eleven-acre solar farm located next to its runway. London Stanstead has appointed EDF Renewables to construct a 14.3MW solar farm to its east.
Airport operators often distinguish between emissions on ground (scope 1 and 2) and emissions in the air (scope 3). The latter accounts for the bulk of their emissions footprint.
“Scope 3 emissions are critical when assessing airports as the account for the vast majority of overall emissions (~95% for Heathrow, for instance) and their inclusion matters for the credibility of SLB structures”, notes David.
Without scope 3 inclusion, greenwashing risks are heightened. Hong Kong airport, for instance, has been accused of using green bond proceeds to finance a new runway. “Labelling this project as green is pure high-flying greenwashing”, warns Reclaim Finance, an advocacy group.
Accountable emissions
Airport operators issuing green debt inevitably encounter a scope 3 conundrum. Link them to bonds and the issuance seems more credible, yet these emissions are often where degree of control is the lowest.
London Heathrow for instance, plans to incentivise airlines to use low emission fleets or fuels through landing charges but acknowledges that this remains largely outside of its control.
To find a way through, operators have deployed varying approaches to emissions accounting. For instance, ADR links two of its latest SLBs with aircraft landing and take-off (LTO) cycles. LTO emissions estimation techniques are being refined, allowing scope 3 emission numbers to be more airport specific.
“This makes the scope of emissions more aligned to airport-specific activities. In our view, it’s also positive to see now a second SLB issuance with the same KPIs, which makes comparability easier”, says David, explaining ADR’s decision to link bonds with LTO emissions.
Whether or not investors buy into new emissions accounting techniques remains to be seen. ADR for instance, has a target observation date coming up in 2027. AFII’s reading of market pricing suggest a high possibility of targets being missed.
As the market for airport green debt matures, demands for minimising greenwashing risks will likely move in tandem. Investors who have been welcoming of such instruments will want to see credibility and accountability take centre stage.
Institutional Investment Conferences & Summits from Longview Networks
