The retention agency obsessed with your bottom line.

We're a small, specialist team that helps 7‑ and 8‑figure e‑commerce brands turn email, SMS and automation into a predictable profit channel. No bloated retainers. No recycled templates. Just senior strategists, designers and copywriters on every account.

OUR STORY

Why we built Inbox OS.

Luc and Cedric met at Cloudpillo: Luc owning the overall email marketing strategy, Cedric on design, copy, and strategy. They kept running into the same frustration: email was treated as an afterthought, owned by whoever had capacity, measured by open rates instead of revenue.

So they built Inbox OS. An agency focused only on email and retention for ecommerce brands doing real volume: strategy, design, copy, and reporting handled end to end, no hand-offs, no generalists, no templated playbooks.

Today they work with 75+ brands from €1M to €50M+ in revenue, still operating like the small, senior team they started as.

Luc de Bruin

CEO · Co-founder

Cedric van der Vlies

COO · Co-founder

OUR PHILOSOPHY

Ads drive growth.
We drive profit.

Three principles guide everything we build, ship and report on.

Specialists, not generalists

If you try to do everything, you end up doing nothing well. We focus on one thing, retention, and surround ourselves with people who are the best in the world at their specific craft.

Strategy before tactics

We don't just ship templates. Every flow, every campaign, every segment starts with a clear strategy mapped to your revenue goals, then we obsess over the execution.

Profit over vanity metrics

Open rates are nice. Attributed revenue pays the bills. We measure what matters, report it honestly and keep pushing until the numbers speak for themselves.

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Think we'd be a good fit?

Book a free 30-minute strategy call. We'll audit your current setup and show you exactly where the revenue is hiding.

No contracts. No pitch. Just strategy.