How to calculate Unsubscribe Rate

Formula

Unsubscribe rate = unsubscribes ÷ emails delivered × 100

SQL query

This example assumes: emails(id, campaign, delivered), unsubscribes(email_id, unsubscribed_at). It is written in PostgreSQL syntax; date functions differ slightly in MySQL, BigQuery and SQLite, and your column names will differ from these.

SELECT e.campaign,
       COUNT(*) FILTER (WHERE e.delivered)                         AS delivered,
       COUNT(u.email_id)                                          AS unsubscribes,
       COUNT(u.email_id) * 100.0
         / NULLIF(COUNT(*) FILTER (WHERE e.delivered), 0)         AS unsubscribe_pct
FROM emails e
LEFT JOIN unsubscribes u ON u.email_id = e.id
GROUP BY e.campaign
ORDER BY unsubscribe_pct DESC;

Common mistakes that make Unsubscribe Rate wrong

• Compare per campaign, not only overall; one badly targeted send can hide in a healthy average.
• Unsubscribes that happen days later are attributed to the wrong send if you only look at the first day.
• Spam complaints are a separate, more serious signal; do not merge them.

Ask for Unsubscribe Rate in plain English

Instead of writing the query yourself, you can type the question. SchemaChat turns it into SQL against your connected database or uploaded file, runs it, and shows the SQL and the figures it used so you can check the answer before you share it. It does not replace your judgement about the definition: check that the query matches the formula your business uses.

• Which campaigns had the highest unsubscribe rate?
• How has the unsubscribe rate trended by month?