Сarving up the competition.




Email Strategy, Email Design, Flows Creation, Campaigns Creation


Subscription Food Box

SeoulBox is a DTC brand that focuses on subscription boxes of unique Korean snacks and k-pop merch. The centrepiece of the company’s marketing efforts was and remains email marketing. That’s where Underground Ecom came in. We utilized strategic retargeting and retention marketing efforts to increase ROI via lowered customer acquisition costs. This method also increased CLTV while meshing well with their subscription business model.


Creating a Smart Lead Magnet Strategy

The different touchpoints that brands maintain with customers are critical. These are all potential opportunities to gather information, increase conversion and deepen engagement and connection. Seoulbox wanted to help craft a smart strategy for Lead Magnets.


To find the the best lead magnet strategy which would balance engagement, with frequency we tested different popup variations. Then we spearheaded implementation and optimization.


A few of key tests included:

  • Lead magnet design styles including popups, fly-outs, and ‘spin-the-wheel’
  • Incentives such as percentage, flat discounts or free shipping. We also experimented with added value incentives (i.e. a free case-study PDF)
  • Countdown timers to increase scarcity of offer
  • Customer journey variations including: revealing the discount before getting and after getting the email address, collecting multiple information fields or just one and where on the site to first engage with the customer. 

A Systematic Plan to Improve Low Click and Low Open Rates

When we began working with Seoulbox, they were seeing both low open and low click rates. We introduced a systematic plan to optimize and improve both metrics. Low click and open rates are indicative of low engagement which ultimately impacts CLTV and business revenues.


Healthy open rates rely on good Subject Lines (SL) and Preview text (PT). We soon made several interesting discoveries in the course of testing. We realized that personalized copy for this client in particular had a good impact on the open rates. We also that hybrid Korean and English subject line which included words from both langues performed best. 

These sorts of insights would have been impossible without rigorous testing. There are near-infinite variables to test. Here are just a few starting points below to test:

  • {{first_name}} or no {{first_name}} in the subject and preview text
  • Revealing a discount or only teasing a discount without the reveal
  • Posing a question or making a statement
  • Using scarcity and urgency language in the subject line and preview text

Click rates are harder to improve. Optimization often requires segmenting out only the most engaged subscribers. Close rate is a key metric that has only become more relevant with the recent introduction of iOS15.

Our work with Seoulbox generated several insights. We realized their audience responded to brighter colour schemes, bigger CTA buttons above the fold, K-Pop stars, and animation.

Our experiments revealed that both scarcity language and Korean cultural content were effective. These findings led us to craft a unique sales approach that ended up tripling their revenue.

Working with the Underground Ecom team has been fantastic. They are a truly professional agency who deliver great results.

Suji Sohn, CEO



The numbers tell an impressive story of revenue growth from email marketing as a result of working with Underground Ecom. In half a year, we see a nearly 3x increase in email revenue growth. We also find a 2x growth in revenue per email recipient. These wins were generated by using a smart pop-up strategy to drive list growth, as well as utilising rigorous testing and personalization experimentation to improve flagging open and click-through rates. Of course, all of these methods rest upon the solid foundation of an amazing working relationship with our partners at SeoulBox.

Email Revenue Growth


Percentage of Total Revenue From Email


Revenue/Email Recipient Growth



Seoulbox started as a shared longing for home. It is now a 7-figure business with a global team and customer base. In 6 months, we have managed to triple Soulbox’s email marketing revenue. Note that $/recipient doubled. Most of the revenue came from campaigns which shows that the existing subscriber list is highly engaged with the brand and is a solid community that will continue to drive repeat business. 

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