51.5% OPEN RATE
AT SERIOUS SCALE

The Account

A health and supplement brand with a large, active subscriber base and a leadership team that understood email was their most profitable channel. When we took over the account, the infrastructure existed but the results were inconsistent. Some campaigns performed. Most underperformed. The automation side was almost untouched.

The goal was straightforward: make the entire email program reliable (not just the occasional good send, but every send, every flow, every automated touchpoint) while growing send volume to match the size of the list.

Campaigns / year: 191    Active flows: 193    Total delivers: 2.4M

The Problem

Scale kills open rates. This is the most predictable pattern in email marketing: as a brand grows its list and increases send frequency, engagement numbers start to drop. Deliverability softens. Inbox placement gets less reliable. Open rates that once hit 40% start drifting toward 20%.

At 191 campaigns per year (nearly four broadcasts per week) and 2.4 million total sends, this account had every condition required for engagement collapse. A large, aging list. High send frequency. No systematic suppression. Automation that wasn’t doing enough lifecycle work to offset campaign fatigue.

The industry benchmark for open rate sits at 25%. Most large health and supplement brands operating at this volume land between 22% and 30%. The question wasn’t whether this account could beat that benchmark: it was by how much, and whether that performance could be sustained across a full year of high-volume sending.

The specific risk: Sending nearly four campaigns per week to a large list without a rigorous segmentation and suppression system means every inbox provider (Gmail, Yahoo, Apple) starts flagging the sending domain. Open rates fall, then deliverability falls with them. The two problems compound. That was the risk this program had to solve.

The System

Four interconnected decisions made the open rate hold at scale. Any one of them alone wouldn’t have been enough.

1. Audience segmentation: no broadcast to the full list. Every campaign defined its intended audience before a single word was written.
2. List hygiene: profiles that hadn’t engaged in 90+ days were funneled into a re-engagement flow before any suppression decision was made.
3. Automation depth: 193 flows running in parallel handled every customer lifecycle stage.
4. Subject lines: tested, not guessed. Short vs. long, curiosity vs. direct, question vs. statement.

The Delta

Quantitative outcomes from 12 months of Klaviyo campaign and flow reporting. A 51.5% average open rate across 2.4 million delivers held across the full year, through 191 campaign sends, at nearly four sends per week. The click rate held well above the 2.5% industry benchmark.

• Avg open rate: 51.5% (+26.5pp above avg)
• Avg click rate: 3.45%
• Emails delivered: 2,365,244 (12 months)
• Campaigns sent: 191 (~4/week)
• Active flows: 193 (full lifecycle)
• Avg flow open rate: 33.2%