Most conversations about airline retailing start with the offer: a new fare family, a loyalty tier, a premium cabin. Fewer start with the question that decides whether any of it works: can the commerce stack underneath sell what got announced. That second question is where the real growth in this industry is concentrating right now. 

 

Ancillary revenue reached $157 billion globally in 2025. That is 15.7 percent of total airline revenue, up from 9.1 percent in 2016 (IdeaWorks, 2025 Yearbook). McKinsey estimates $45 billion of that category is still unclaimed industry-wide by 2030. The category is growing. The growth is not evenly spread. 

 

Loyalty is the largest single piece of it. Loyalty and co-branded cards already make up 40 to 50 percent of ancillary revenue at legacy carriers (IdeaWorks, 2025 Yearbook). Most of it comes through co-brand card remuneration. Carriers actively expanding their programs are seeing that remuneration grow 20 to 25 percent year over year. That is according to Q2 2026 investor disclosures across multiple carriers. The mechanism is straightforward. A bank pays for access to a loyal customer base, and the airline gets paid for building that base. 

 

Premium seating is the second concentration. Ancillary revenue share attributable to seating alone ranges from 3.2 to 62 percent across carriers (IdeaWorks, 2025 Yearbook). Same products. Comparable passengers. Premium economy capacity has grown more than 30 percent industry-wide since 2019, even through the pandemic disruption (OAG, 2023). The spread between the low and high end of that range has less to do with the seat. It comes down to what happens at the moment a customer decides whether to pay for it. 

 

IATA’s Airline Retailing Maturity index breaks the category into six domains: shop, order, pay, settle, account, and setup. Most of the public attention, and most of the vendor spend, goes to the first one, creating and pricing the offer. The domains after it carry real revenue and almost no public benchmark yet. How the order gets serviced. How the payment settles. Who owns the product catalog. Roughly one in four airlines have started work there. There is no shared scoreboard for it yet, the way there is for TRASM or load factor. 

 

Our view, from the carriers we work with, is that the sequencing is backwards more often than the technology is wrong. A tier gets announced before the points engine can express it. A premium cabin gets built before the checkout can compare it against the base fare in real time. The fix is rarely a new platform. It is naming a single owner for the product catalog before the next initiative launches without one. It is building the offer and tier logic above whichever reservation system is already in place, Sabre, Amadeus, or Navitaire. 

 

The carriers closing this gap are not necessarily the ones with the largest ancillary number today. They are the ones treating the commerce layer as a standing discipline, not a project attached to whichever product launches next.