How to Choose Gmail vs SMTP and Select Sending Inboxes

Gmail vs SMTP

When creating or editing a campaign, you choose how to send: Gmail (accounts you connected in Settings → Integrations) or SMTP (domain inboxes you added in Inbox Accounts after verifying your domain).

Gmail — Quick to set up; good for personal or small-team outreach. You connect Gmail via OAuth or App Password in Settings → Integrations → Gmail. Each connected account appears as an inbox you can select in the campaign.

SMTP — Send from your own domain (e.g. sales@yourcompany.com). You must verify the domain in Domains and add SMTP inboxes in Inbox Accounts. Then you can select those inboxes when the sender type is SMTP.

How to choose in a campaign

1. Open Campaigns → New campaign or Edit an existing one.
2. Find the Sender or Sending from section.
3. Select Gmail or SMTP:
   • Gmail — The list shows all Gmail accounts you connected. Select one or more; the campaign will send from these (with rotation if multiple).
   • SMTP — You may need to select a domain first; then select one or more SMTP inboxes for that domain. Only inboxes in Ready (or allowed) status should be used.
4. If you have multiple inboxes, set sender rotation (e.g. round-robin or random) so sends are spread across them.

Tips

• Use Ready inboxes; avoid Warm up required or Warning unless you stay within warmup limits.
• For small lists, using fewer inboxes can be better for reputation; for large lists, spreading across more inboxes helps with daily limits.
• You can run a test send (if the campaign form has it) to confirm the selected inbox works before launching.