The $2 Insert That Outsells Our Best Ad

We ran an experiment with a portfolio company last quarter that I can't stop thinking about. They were spending about $120K a month on paid acquisition across Meta and Google. Decent ROAS, nothing spectacular. Standard DTC growth engine.

At the same time, we designed a custom packaging insert for them at Paking Duck. A simple card — heavy stock, soft-touch finish, about the size of a postcard. On one side, a QR code to a "secret" landing page with 15% off the next order. On the other side, a single line: "We made this for you. Tell a friend." Below that, a unique referral code.

The insert cost $1.80 per unit all-in — design, printing, and fulfillment.

After 90 days, they tracked the numbers. The referral codes on those inserts generated $340K in attributed revenue. The QR code reorder page had a 31% scan rate and a 22% conversion rate. Combined, that $1.80 insert was responsible for more new customer revenue than their entire Google Ads budget.

And it's not even close when you look at the quality of those customers. Referred customers had a 40% higher average order value and were 3x more likely to make a second purchase within 60 days. They came in warm because a friend told them about the brand. No cold audience targeting required.

I've been in the packaging business long enough to know that inserts aren't a new idea. But most brands do them wrong. They stuff a generic discount code on a flimsy slip of paper that goes straight in the trash. Or worse, they include a novel-length brand story that nobody reads.

The ones that work share three traits. They feel like part of the product, not an ad. The paper stock matters. The design matters. If it looks like junk mail, it gets treated like junk mail. They have a single, clear action. Not three QR codes and two URLs and a social handle. One thing to do. Scan this. They leverage the emotional high point. The customer just opened a package they're excited about. That's the single best moment to ask for a referral or a repeat purchase. Their guard is down and their satisfaction is up.

We're now building custom insert programs for a dozen brands at Paking Duck. The ROI is so consistently strong that I'm genuinely surprised more brands don't treat packaging inserts as a primary marketing channel instead of an afterthought.

Your box already gets opened. The attention is free. What you do with that attention is the difference between a $1.80 expense and a $1.80 investment.