For travel agents, the cheapest airfare can be the easiest fare to sell, and sometimes the hardest to explain later.
The reason is simple: the price displayed at the beginning of a search increasingly represents only the core transportation. Baggage, seat selection, flexibility and other services can move the final cost considerably higher.
Ancillaries are no longer small change
Globally, airlines generated an estimated US$148.4 billion in ancillary revenue in 2024, according to IdeaWorksCompany. The figure was forecast to rise to US$157 billion in 2025, more than double the US$67.4 billion recorded in 2016.
Ancillary revenue accounted for about 15.7% of airline revenue in 2025, compared with just 9.1% in 2016. Depending on the airline, the proportion ranges from only a few per cent to more than half of total revenue.
IATA separately forecast US$144 billion in ancillary revenue in 2025, up 6.7% from the previous year, alongside US$693 billion in passenger revenue.
The numbers explain why airlines have increasingly separated the basic fare from additional services.
What it looks like on a Nairobi itinerary
Consider a hypothetical return journey from Nairobi to a European destination.
An agent finds a basic return fare of US$520. It looks like the obvious option when compared with another fare priced at US$590.
But suppose the US$520 fare does not include a checked bag. Adding one for both directions costs US$100. The passenger wants a selected seat on both flights at US$25 each way, adding another US$50.
The apparent US$70 saving has now disappeared.
Basic fare: US$520
Checked baggage: US$100
Seat selection: US$50
Final cost: US$670
The alternative fare at US$590 could therefore be US$80 cheaper in the final transaction, depending on what it includes.
The figures are illustrative, not current market prices. The point is the calculation: the lowest base fare is not necessarily the lowest total price.
The problem for agents
This creates a difficult conversation at the point of sale. A customer searching online may see a fare advertised at US$520 and ask an agent why the agency is quoting US$670. The answer may be that the two prices are not selling the same product.
For an agent, therefore, fare comparison increasingly means comparing what is included, not just what appears next to the flight number.
That is particularly important for business travellers, families and passengers carrying checked luggage. A traveller who needs baggage, a specific seat and flexibility may have little interest in the absolute cheapest fare.
NDC changes the shopping experience
This is also where NDC becomes relevant. The standard allows airlines to distribute richer offers and ancillary products rather than limiting the transaction to a traditional fare and schedule display.
For agents, that can mean more information, but also more variables.
Two fares for the same Nairobi–Europe itinerary may differ in baggage allowance, seat conditions, changeability, refundability and other inclusions.
The agent therefore has to interpret the offer rather than simply identify the lowest number.
The revenue is becoming material
The growth in ancillary revenue shows why this model is unlikely to disappear.
Global ancillary revenue increased from US$67.4 billion in 2016 to US$148.4 billion in 2024, an increase of roughly 120%. The 2025 forecast of US$157 billion would put the industry more than US$89 billion above its 2016 level.
And ancillary revenue is not limited to baggage. IdeaWorks includes seat selection, onboard food and other a-la-carte purchases, as well as wider revenue streams such as hotel, car-rental and co-branded card partnerships.
For airlines, the attraction is obvious: the base fare can remain competitive while passengers pay separately for products they value.
What agents should be selling
The lesson is not that agents should stop looking for the lowest fare.
It is that the lowest fare should be the beginning of the comparison, not the end of it.
For agents, the more useful question is increasingly: What will this passenger actually need?
A passenger travelling for two weeks with checked luggage has different requirements from someone travelling with hand baggage only. A corporate traveller may value flexibility more than saving US$50. A family may place greater importance on sitting together.
The agent’s value therefore moves beyond finding a fare.
It is in explaining the difference between the fares and calculating the cost of the journey the customer is actually trying to buy.
As airlines generate an increasing share of revenue from services outside the basic ticket, that distinction is becoming an increasingly important part of selling air travel.
