SMTP / IMAP + ColdSend
Connect any SMTP or IMAP inbox to ColdSend. Use ColdSend's sequencer and reply tracking with mailboxes from any provider or host.
How it works
Gather SMTP and IMAP credentials
Collect the server, port, username, and password for each mailbox you want to connect.
Add an SMTP/IMAP sender account
In ColdSend, go to Sender Accounts, choose SMTP/IMAP, and enter the credentials for your mailbox.
Verify and send
ColdSend will test the connection. Once verified, select the inbox in a campaign and start sending.
Need detailed setup steps?
The Custom SMTP Inbox Setup Guide walks through connecting a single inbox or bulk-importing many via CSV.
Why connect SMTP/IMAP to ColdSend?
SMTP/IMAP is the most flexible way to connect mailboxes. It works with any host that supports standard email protocols, including private servers, niche providers, and inboxes created through other infrastructure tools.
It's the best choice if you already own inboxes elsewhere, want full control over where they are hosted, or need to connect a provider ColdSend does not have a native OAuth integration for yet.
Who is this for?
Teams with existing mailbox portfolios, agencies moving clients from other sequencers, and senders using custom infrastructure that exposes SMTP/IMAP credentials.
What you get
Bring any mailbox that supports SMTP and IMAP. ColdSend does not restrict you to specific providers or hosts.
Upload dozens of inboxes at once with server, port, username, and password. ColdSend validates credentials automatically.
Replies are fetched through IMAP and surfaced in ColdSend's unified inbox alongside your other sender accounts.
SMTP/IMAP accounts count toward your plan's sender limit with no extra per-inbox charge from ColdSend.
Ready to connect?
Start sending from SMTP / IMAP in minutes, or open the setup guide if you need help with credentials or OAuth.
Need help? Book a call with our team.
Related integrations
Google Workspace
Connect Google Workspace mailboxes to ColdSend. Send cold emails through your own OAuth app or ColdSend's shared infrastructure with native reply tracking.
Microsoft 365
Connect Microsoft 365 and Outlook mailboxes to ColdSend. Send cold emails through your own Microsoft Entra OAuth app or ColdSend's shared infrastructure with native reply tracking.
without the infra.
