Definition
The campaign payback period answers: how many conversions does this campaign need to be profitable? It accounts for every cost — platform fees, design time, copywriting, development, testing, and list management.
Formula
Payback Period (conversions) = Total Campaign Cost / (Average Order Value × Gross Margin)
For example, a campaign costing £500 with an AOV of £50 and 40% margin needs 25 conversions to break even: 500 / (50 × 0.40) = 25.
Why It Matters
Knowing your payback number before you send changes how you evaluate campaign performance. A campaign that generates 20 conversions might look unsuccessful on its own but could be highly profitable once you factor in the lifetime value of those new customers. The payback period gives you a clear baseline for go or no-go decisions.
Related Glossary Terms
A/B Testing
A/B testing in email marketing is the practice of sending two variations of an email to a small sample of your list to determine which version performs better before sending the winner to the remaining subscribers.
Announcement Email
An announcement email is a dedicated campaign that communicates a specific update, milestone, or change to subscribers, from product launches and feature releases to company news and events.
ARPU (Average Revenue Per User)
ARPU (Average Revenue Per User) is a metric that measures the average revenue generated per email subscriber over a specific period, used to evaluate list value and campaign effectiveness.
Attention Rate
Attention rate is the percentage of email opens that last longer than 5 seconds, distinguishing genuine reads from passive opens, preview-pane views, or Apple MPP auto-loads.
B2B Email Marketing
B2B email marketing targets business professionals and organisations with longer sales cycles, educational content, and relationship-driven campaigns compared to B2C email.
B2C Email Marketing
B2C email marketing focuses on sending targeted promotional and transactional emails to individual consumers, emphasising personalisation, urgency, and direct response.