Custom Content Block Testing

Beyond subject lines, hero blocks, and CTAs, most emails contain content blocks that showcase products, collections, or editorial content. These blocks often drive the majority of click-throughs and revenue, yet they are rarely tested systematically.

What counts as a custom content block?

Any modular section of your email that can be swapped between variants:

• Promoted products: a curated grid of items you want to highlight
• Featured collections: “New arrivals”, “Back in stock”, “Editor’s picks”
• Social proof blocks: customer reviews, UGC, or “bestsellers” sections
• Editorial content: brand storytelling, how-to guides, lifestyle imagery
• Offer layouts: different ways to present the same promotion (single hero product vs multi-product grid)

How liftstack handles content block testing

• Create a snippet for each content block position in your email template
• Add 2–3 variants with different content strategies (e.g. personalised recommendations vs editorially curated vs trending items)
• Set revenue per exposure or conversion rate as your primary metric
• Results are available after a single campaign send for audiences of 30K+

Why content blocks are high-leverage

Subject lines determine whether someone opens. Hero blocks set the tone. But content blocks are where browsing turns into buying. A well-chosen product grid or collection feature can shift revenue per send meaningfully, and because these blocks appear in every campaign, improvements compound across every send.

Getting started

Pick your highest-revenue email template and identify the main product or collection block. Create three variants: your current approach (control), a personalisation-driven alternative, and a curation-driven alternative. One campaign is usually enough to get a clear signal on which strategy your audience prefers.