Email Specs
Email Sending Frequency Reference
There is no correct sending frequency, only a frequency your list tolerates at your unsubscribe and complaint rate. This page gives the starting points I use and the signals that tell me to speed up or back off, plus the warm up schedule shape for a new sending domain.
| Programme | Common cadence | Watch |
|---|---|---|
| Newsletter, B2B | Weekly or every two weeks | Unsubscribe rate and reply volume |
| Newsletter, consumer | Weekly to several times a week | Complaint rate |
| Ecommerce promotional | 2 to 5 per week in season | Revenue per email, not open rate |
| Onboarding sequence | Every 1 to 3 days for the first weeks | Completion of the sequence |
| Re-engagement | A short finite series | Suppress at the end either way |
| Transactional | Triggered, no cap | Keep separate from marketing streams |
| Stage | Approach | Notes |
|---|---|---|
| Week 1 | Small volume to the most engaged segment | Prove authentication is passing |
| Weeks 2 to 4 | Increase gradually, roughly doubling | Hold if complaints rise |
| Weeks 4 to 8 | Expand toward full list volume | Add less engaged cohorts last |
| Ongoing | Keep volume steady week to week | Spikes look like compromise |
Notes
Cadence should be set by segment, not by the list. Your most engaged 20 percent will happily take several emails a week, and your dormant tail should get almost nothing because sending to it is what damages reputation. One frequency for everyone means you are simultaneously under mailing your best subscribers and over mailing your worst.
Judge frequency changes on revenue and complaint rate per period, not on open rate per send. Open rate falls when you send more often and total revenue can rise at the same time. Apple Mail Privacy Protection has also made open rate an unreliable measure on its own, so anchor the decision to clicks and outcomes.
Give people a preference centre with a lower frequency option before the unsubscribe link. Downgrading a subscriber to monthly keeps a relationship that a hard unsubscribe ends permanently, and it reduces spam complaints, which cost far more than an unsubscribe does.
Mailbox provider requirements for bulk senders, including complaint rate thresholds and one click unsubscribe, have tightened in recent years and continue to change. Check the current Gmail and Yahoo sender requirements before scaling volume.
Frequently asked questions
How do I know I am sending too often?
Complaint rate rising toward 0.1 percent, unsubscribes climbing send over send, and revenue per email falling faster than volume rises. Any two of those together is the signal to cut back.
How long does warming up a new domain take?
Typically four to eight weeks to reach meaningful volume, depending on list quality and how engaged the early cohorts are. Rushing it is the most common cause of a new domain landing in spam.
Official sources
Platforms change specifications without notice. Check the primary documentation before a launch that depends on an exact value.
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