List Hygiene

A clean list is the single highest-impact thing you control as a sender. ISPs use engagement signals (opens, clicks, and absence of complaints) to decide where your email lands.

Double Opt-In

Double opt-in requires subscribers to confirm their email address before being added to your list. It eliminates typos, disposable addresses, and people who did not actually want to subscribe.

graph LR
    A[User submits form] --> B[Send confirmation email]
    B --> C{User clicks confirm?}
    C -- Yes --> D[Add to active list]
    C -- No / Timeout --> E[Discard address]

Implement this by sending a confirmation email via send-email/instant with a unique token link. Only add the contact after the token is verified.

Regular Cleaning Cadence

Run these removals on a scheduled basis (monthly recommended):

Keplars automatically suppresses bounced and unsubscribed contacts. The 6-month inactive purge is something you manage based on your engagement data.

Re-Engagement Before Removal

Before removing cold subscribers (no opens or clicks in 6 months), send a targeted re-engagement campaign:

1. Segment contacts with no engagement in 180 days
2. Send a single "still interested?" email with a clear CTA
3. Wait 2 weeks
4. Remove everyone who did not engage with that email

This recovers a small percentage of genuinely interested subscribers while keeping your list clean.

Segment by Engagement

Use Keplars audiences to separate your list into engagement tiers and adjust send frequency accordingly: