top of page
  • Fernando Montoro

Advanced Virtual Interlining - Part 1

Updated: May 10, 2022

Virtual Interlining (VI), also known as Self-Transfer or Self Connect fares, is a relatively new way of providing better fares and more options to travellers, while providing a new source of revenue for Online Travel Agencies (OTA). You can read all about TripStack’s Virtual Interline platform here.

In this post we will concentrate on some of the advanced features of the product that include Airport Transfers and Multiple-Transfers in a single itinerary.

Airport Transfers

An airport transfer is a Virtual Interlining itinerary where the traveler has to transfer between 2 airports (in the same city). I think it is best to represent this with an example;

Imagine that you are flying from Edinburgh (Scotland) to Montreal (Canada). The most common route would be to fly from Edinburgh’s main airport, Turnhouse (EDI), to London’s largest and most international airport, London Heathrow (LHR), and from there take a long-haul connection with British Airways or Air Canada to the beautiful city of Montreal.

But who said that the most common itinerary is the best one? After a few checks in flight meta search engines such as Kayak or Skycanner you would realize that you could catch a flight from Edinburgh’s Turnhouse (EDI) to London City (LCY) and transfer to London Gatwick (LGW) to take a flight to Montreal (YUL). As you can see in the example below, the traveler has 3h+ to get from London City (LCY) to London Gatwick (LGW) to make the connecting flight. This flight is on average ~ $500 USD cheaper and 4 hours faster than the non-VI alternatives. It also appears as the best possible itinerary in Kayak.

The screenshot shows a Virtual Interline itinerary with an airport transfer between the London City (LCY) airport and London Gatwick (LGW)
Airport Transfer Example

There are around 278 cities in the world that have multiple commercial airports (the so-called Metro Codes). Examples of these cities include:

  • London - Heathrow (LHR), Gatwick (LGW), Luton (LTN), Stansted (STN), City (LCY)

  • Milan - Malpensa (MXP), Linate (LIN), Bergamo (BGY)

  • Miami - Miami (MIA), Fort Lauderdale (FLL)

  • Paris - Charles de Gaulle (CDG), Orly (ORY), Beauvais-Tillé (BVA)

  • New York - John F. Kennedy (JFK), La Guardia (LGA), Newark (EWR)

  • Tokyo - Narita (NRT), Haneda (HND)

While having multiple airports in a city is a great thing, the challenge is that many of these airports focus on either long-haul international flights or short-haul domestic flights. In addition, Low-Cost Carriers (LCC) tend to fly to the domestic airports and flagship carriers fly in and out of international airports, which makes connecting small and large cities in different parts of the world very difficult. While most companies see this as a problem, at TripStack we see this as an opportunity to simplify complexity. Knowing that our passengers could do a short 1-2 hours commute within the same city, very often using public transit, our algorithms are able to create thousands of new itineraries that wouldn’t exist otherwise. The benefit is clear; cheaper and faster itineraries to get to your desired destination that will save the traveler hundreds of dollars and in some cases lead to the best connection in terms of duration and cost.

Airport Terminal
Airport Terminal

To make it even better, and to ensure a great customer experience, TripStack has spent a lot of time making sure that the traveler has plenty of time to commute between the 2 airports, even while using public transportation, without missing the flight. We do this by taking commute times, hourly traffic patterns and other factors, such as the size of an airport, into consideration. TripStack also adds a buffer to account for any unexpected delays, and in an unfortunate case of a missed connection, TripStack has the passenger covered with our Self-Transfer Guarantee that is included in the price of the VI itinerary.

Virtual Interlining (VI) with Multiple Self-Transfers

Virtual Interlining with multiple self-transfers is an extension of traditional Virtual Interlining (with a single transfer). Multiple transfers are really important for long haul flights as well as itineraries that include secondary or tertiary locations.

For example, if you live in a medium sized city such as Montpellier (MPL) in France or San Diego (SAN) in California and want to take a much-deserved holiday in Cancun (CUN), Mexico chances are that you won’t be able to fly directly to Cancun from either San Diego or Montpellier. You may be able to get to Cancun by flying a normal Virtual Interlining itinerary such as Montpellier (MPL) – Paris (CDG) – Cancun (CUN). However, this connection may not always be possible every day of the week, or it may not be the cheapest or the best option. A great example would be Montpellier (MPL) – Paris(ORY) – Madrid (MAD) – Cancun (CUN).

The screenshot shows an itinerary with multiple self transfer locations (2).
Multiple Self-Transfer VI Itinerary Example

Advanced features such as Airport Transfers and Multiple Transfers simply add more options and often unique options for Online Travel Retailers, providing additional revenue opportunities and cheaper fare for travellers.

To find out more please reach out to

510 views0 comments

Recent Posts

See All


bottom of page