Definition
Email revenue retention measures the percentage of revenue from existing email subscribers that is retained from one period to the next. It tracks how much of the revenue generated by a cohort of subscribers carries forward, isolating the recurring contribution of existing customers from revenue added by new subscribers. Revenue retention is a key indicator of list health and the long-term value of an email program.
How It Works
Revenue retention looks at a starting set of subscribers and asks how much revenue they still produce in a later period. This distinguishes durable revenue from one-time or newly acquired revenue.
- Cohort-based view — the metric follows a specific group of subscribers forward, rather than comparing whole-period totals.
- Retained versus new — expansion and repeat purchases from the same subscribers count as retained revenue, while brand-new subscribers do not.
- Churn and contraction — revenue lost to unsubscribes, inactivity, or reduced spending lowers the retention figure.
Revenue retention is the revenue counterpart to subscriber retention, and it is a leading input to subscriber-ltv calculations and to the assessment of net revenue retention in email-roi style metrics.
How to Calculate
Calculate revenue retention in four steps:
- Identify the starting cohort — select the subscribers active at the start of the period.
- Measure starting revenue — record their revenue in the initial period.
- Measure retained revenue — record the same cohort's revenue in the following period.
- Divide — divide retained revenue by starting revenue and multiply by 100.
Revenue Retention = (Retained Revenue / Starting Revenue) x 100
| Variable | Description |
|---|---|
| Retained Revenue | Revenue from the starting cohort in the later period |
| Starting Revenue | Revenue from the starting cohort in the initial period |
Example
A brand's existing subscribers generated £100,000 in January. In February, the same subscribers generated £82,000. Dividing £82,000 by £100,000 gives a revenue retention of 82%, indicating modest churn and contraction that the brand investigates by segment.
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Frequently Asked Questions
Customer retention measures the share of subscribers who remain, while revenue retention measures the share of revenue that carries over. Revenue retention also captures expansion and contraction, so it can exceed or fall below customer retention.
Yes. When existing subscribers increase their spending through upsells and cross-sells, retained revenue can exceed starting revenue, producing retention above 100%. This is a sign of healthy expansion.
It reveals whether the email program is building durable value or merely replacing lost revenue with new acquisition. High retention supports strong subscriber-ltv and reduces dependence on constant list growth.
Subscriber churn, disengagement, reduced purchase frequency, and increased competition all lower retention. Segmenting by behaviour helps identify which groups are contracting.