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Celtic & Co was founded 26 years ago and was the original holder of the UGG trademark in the UK. The business is still an independent online boutique family-run company focused on selling sheepskin slippers, boots, knitwear and outerwear. Celtic & Co is built on these core brand principles:

  • Casual luxury at affordable prices
  • British manufacturing
  • Natural, organic and sustainable materials



  • Develop testing strategies to further understand the lifetime value of a customer.

The Challenge

Celtic & Co’s biggest challenge is seasonality. The main fabric used in their products is sheepskin for items like slippers, boots or coats. These sell well in the winter and colder months, but are more challenging to sell during the rest of the year. Celtic & Co, therefore, need to make sure they make the most of the email channel at key times to maximize engagement and conversions.


The Solution

To further develop the understanding of the customer, Celtic & Co implemented several testing plans designed to gain insight into the best time of day to send email, as well as the best type of messaging, offer and content.

  1. Time of Day

Celtic & Co tested three different launch times throughout the day (10am, 2pm and 6pm) to understand the effect this would have on conversion rates.

  1. Price Messaging

Celtic & Co wanted to understand whether including prices in their emails would encourage or deter subscribers from clicking through. They tested one variant with the price included in the call-to-action button and one with no prices mentioned whatsoever.

  1. Type of Offer

As getting the subject line right is a key part of a successful re-engagement program, Celtic & Co wanted to see which one would be the best to encourage customers to engage again and purchase. The content of the email was the same, offering a discount of 10% and free delivery. The variants tested were:

  • A straightforward offer: “Can We Tempt you Back | Free Scarf Worth £40”
  • A mysterious offer: “We Miss You – Can we tempt you with this special offer?”
  • A fun message: “Is It Time to Say Goodbye? Don’t Forget 10% Off and Free Delivery”
  • An alternative offer: “Don’t Give Us the (Sheepskin) Boot | 10% Off and Free Delivery”
  1. Type of Content

As part of their ongoing newsletter strategy, Celtic & Co tested the impact of not using overtly promotional content. The emails in this test had a blend of inspirational graphics for different looks and styles, Cornish highlights and facts, and information on the heritage of the company.

The Result

For the send time optimization test, Celtic & Co experienced the highest conversion rate (5.3%) with the emails sent at 10am but higher open and click-through rates later in the day, making 6pm the optimum time to send emails for revenue generation.

Despite conventional wisdom often showing that emails perform better without prices, the Celtic & Co. price messaging test showed considerably higher conversions for emails with the price included in the CTA button at 8.5% click-to-sale rate. This was 84% higher than the alternative.

Using a blend of content for newsletters resulted in brilliant increase in CTOR rate of 8.9% to 11%. Compared to the usual product listing emails, revenue per email was up by 92% driven by doubled average order values. This means that Celtic & Co have found their sweet spot of blending inspirational content that customers engaged with and encouraged to spend more on the site.

Finally, by testing the different subject lines and offers with the re-engagement program, they have learned that the highest converting message was the mysterious offer delivering an incredible 16.7% conversion rate.


higher click-to-sale rates