Case study

Thomas Cook Airlines

Throwing out the kitchen sink

Ancillary business

The value of design isn't only in graphics. In this project we proved that less visual design can both improve the customer experience and provide a step change in ROI.

Products that were once a value-add to airline fares, like reserved seats, extra luggage, and food, are now optional extras. In the airline industry, these are called ancillaries. Margins are higher on ancillaries than on the ticket itself.

Email is a crucial inbound marketing channel. After booking a flight, emails must engage customers, and draw them to ecommerce sites and apps where ancillaries are sold. Thomas Cook had neglected design thinking in it’s post-booking email strategy. I saw an opportunity and took it.

What I did

  • UX design
  • Design strategy
  • Content strategy


Click conversion over existing design

open rate

channel revenue YOY

incremental revenue in 10 months


Question the status quo

The status quo

The existing campaign had low open rates averaging less than 9% and sales conversion below 0.35%. With such a low open rate, there was a fear from the marketing team that a customer might miss a promotion if it was only included in one or two emails. The accepted design solution to this problem was to send identical emails with every ancillary product promotion included. The kitchen sink approach.

We saw disappointing figures across the whole campaign. Customers had learned that the emails were virtually identical, and full of sales messages instead of useful information. Trust dropped to zero—and they junked future emails.

They emails were taking a lot of resource from designers, developers, copywriters, and translators. A poor return on investment

A text only test

I hypothesised that the graphics weren’t adding much value for customers, and may even be reducing comprehension. The marketing team required proof that a low-graphics solution might be more effective.

To test the two extremes, I removed all graphical promotions from the email that promoted seat reservations. The text-only approach gave us the opportunity to introduce a more strict hierarchy in the content — allowing us to front-load the messaging in an inverted-pyramid hierarchy.


Find & use valuable content

Copy-first design

The copy became the primary content in the text-only design. We paid a lot more attention to it. From our research we knew that our customers often get confused about seating policies.

  • The email subject and headline teased the content in a vague but serious way that we knew would grab attention.
  • We added value by explaining the seating policy, which was slightly different to other airlines.
  • We presented the options and benefits of reserving seats in context with the policy.
  • We decided not to mention specific prices or discounts, as we felt they would dilute the tone.

Sales messages have been proven to be less credible. And the the existing seating policy copy was impersonal:

All passengers who have not prebooked seats will be allocated seat numbers at check in.

I defined a more personal approach, whihc was much more consistent with the brand:

You can reserve seats up to 24hrs before flying. If you decide not to reserve seats then we’ll assign them on the day.

Call & response

Thomas Cook customers are infrequent flyers. The informational needs of holidaymakers are greater than with regular airlines. With the unbundled nature of the product, there were plenty of opportunities to clarify policies around ancillaries. The strategy—combining helpful content with calls to action—could be repeated across the whole campaign; for seat reservations, baggage allowance upgrades, in-flight meals and more.

By consistently offering value, the emails create a feedback loop of positive sentiment which could reverse the trend in open rates.


Hack the A / B test

Test results

The marketing team were migrating to a platform with A / B testing capability. It wasn't ready in time for this test. I had to get creative with the implementation. I split the test cohorts based on whether the booking number was even or odd and partnered with a data analyst to extract the results from the bookings database.

We discovered the channel click conversion rate had leapt by 40% on the text-only email and had continued rising. The test performed so well that the marketing team immediately switched strategy to converting all the emails to the text-led design. 10 months later, we saw overall ancillary revenue from emails quadruple.

Positive side effects

An unexpected effect was that we saw an increase in cross-sales. When I restricted each email to one subject, I expected sales of individual ancillaries to become more focused. Counter-intuitively, customers were reacting to all emails to book all ancillaries.

This showed that the emails should never be designed in isolation. Trust works broadly across a customer experience. Emails are part of a continuous conversation with customers in a variety of channels. Building trust with valuable content is key to engaging customers.

One message might seed the intention to buy, but it might be the next message that reminds them to act.

RIP Thomas Cook

The 200-year old Thomas Cook Group ceased trading in 2019. The package holiday business struggled to recover from debt generated by a controversial acquisition a decade earlier. To the end, the airline remained one of Thomas Cook's only profitable subsidiaries. I feel proud to have contributed to it's success.

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