Definition
List churn rate (also called list decay or list attrition rate) measures the percentage of email subscribers who leave your list during a given period. Subscribers can be lost through voluntary unsubscribes, hard bounces, spam complaints, or through automated removal due to prolonged inactivity. Churn is a natural part of email marketing — all lists decay over time as people change email addresses, lose interest, or disengage.
The industry average email list churn rate is approximately 0.2% to 0.7% per month, or roughly 20% to 30% per year. High churn rates indicate problems with list quality, relevance, sending frequency, or subscriber expectations. Managing churn effectively is critical to maintaining a healthy, engaged email list.
Formula
List churn rate is calculated by dividing the total number of subscribers lost in a period by the total subscriber count at the start of that period.
List Churn Rate = (Subscribers Lost in Period / Subscribers at Start of Period) × 100
| Variable | Description |
|---|---|
| Subscribers Lost | Total unsubscribes + hard bounces + spam complaints + inactive removals |
| Subscribers at Start | Total active subscribers at the beginning of the measurement period |
Average Benchmarks
| Industry | Monthly Churn Rate | Annual Churn Rate |
|---|---|---|
| Ecommerce | 0.5% - 1.5% | 30% - 50% |
| SaaS & Technology | 0.3% - 0.8% | 20% - 35% |
| Media & Publishing | 0.2% - 0.5% | 15% - 25% |
| Finance | 0.2% - 0.6% | 15% - 30% |
| Healthcare | 0.2% - 0.4% | 12% - 20% |
| Nonprofit | 0.3% - 0.7% | 18% - 30% |
A healthy monthly churn rate is below 0.5%. Rates above 1% per month warrant investigation into list quality, sending practices, or content relevance. However, zero churn is not a healthy sign either — it may indicate you are not cleaning inactive subscribers from your list.
How to Reduce List Churn Rate
- Set proper expectations at signup: Tell subscribers what type of content to expect, how often you will send, and what value they will receive. Mismatched expectations are a leading cause of early unsubscribes.
- Use a preference centre: Let subscribers choose their email frequency and content topics. Giving control over what they receive reduces the likelihood they will unsubscribe entirely.
- Monitor engagement and sunset inactive subscribers: Automatically remove subscribers who have not opened or clicked in 90-180 days. Sending to disengaged subscribers increases complaints and bounces, accelerating churn.
- Optimise send frequency: Too many emails is the number one reason subscribers unsubscribe. Test different frequencies and monitor unsubscribe rates to find the sweet spot for your audience.
- Segment and personalise: Irrelevant content drives churn. Use behavioural data to send targeted emails that match each subscriber's interests and stage in the customer lifecycle.
- Run re-engagement campaigns: Before removing inactive subscribers, send a re-engagement campaign with a compelling incentive. Win back even 5-10% of at-risk subscribers to meaningfully reduce overall churn.
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.
Abandoned Cart Email
An abandoned cart email is an automated message sent to customers who added items to their online shopping cart but left without completing the purchase. It is one of the highest-converting email types in ecommerce.
AMP for Email
AMP for Email is a Google-developed framework that allows email messages to include interactive elements like forms, carousels, accordions, and live content. It turns static emails into dynamic, interactive experiences directly inside the inbox.
Bounce Rate
Email bounce rate is the percentage of emails that were rejected by the receiving server before reaching the recipient. It is a key indicator of list health and data quality.
CAN-SPAM Act
The CAN-SPAM Act is a US law that sets rules for commercial email. It requires accurate subject lines, a physical address, a clear opt-out mechanism, and prompt processing of unsubscribes. Violations can result in penalties up to $51,744 per email.
Click-Through Rate
Click-through rate (CTR) is the percentage of email recipients who clicked one or more links in your email campaign. It measures how compelling your content and call-to-action are.
Frequently Asked Questions
Unsubscribe rate measures only voluntary opt-outs. Churn rate is broader — it includes unsubscribes, hard bounces, spam complaints, and inactive-removal events. Churn rate gives a more complete picture of list health because it captures all the ways a list loses subscribers, not just the ones who actively unsubscribed.
To maintain a steady list size, you need to acquire new subscribers at a rate equal to or greater than your churn rate. If your churn rate is 0.5% per month, you need at least 0.5% list growth per month to stay flat. Most healthy email lists grow by 1-3% per month to offset churn and achieve net growth.
Not necessarily. High churn can be a sign of healthy list hygiene if you are aggressively removing inactive subscribers. A list that never loses subscribers may be a list that never cleans itself — leading to low engagement, high complaint rates, and poor deliverability. The goal is not zero churn but healthy, intentional churn.
Calculate list churn rate monthly for most reporting purposes. Monthly calculation gives you a current view of list health and allows you to spot trends before they become problems. Annual churn rate is useful for year-over-year comparisons and strategic planning.
Common causes include: sending too frequently (especially after increasing send cadence), sending irrelevant content to a segment, a B2B list experiencing turnover, changing ESPs (which can increase bounces), data quality issues (like buying a list), or sending a re-engagement campaign that results in many unsubscribes.