People ask this in three different ways.
Below we answer each one, so you know exactly what is (and isn’t) possible today and after our API ships.
“Can I point my domain to ColdSend but send the mail from another platform?”
No. The moment you delegate your domain to ColdSend we host all authentication records (SPF, DKIM, DMARC) on our name-servers. Because the private DKIM keys never leave our environment, no external sender can sign mail on your behalf without breaking authentication.
If you need to split traffic, keep the domain at a neutral DNS host (Cloudflare, Namecheap, etc.) and add the records manually for each platform — exactly what ColdSend is designed to save you from.
“Can I pipe ColdSend mailboxes (SMTP/IMAP) into Instantly, Smartlead, Reply.io, etc.?”
Also no. ColdSend mailboxes are not exposed via SMTP or IMAP credentials; they work only through our closed API/UI. The same restriction applies in reverse: Instantly, Smartlead, etc. do not let you export their mailboxes either.
“Will the upcoming ColdSend API (Nov 2025) let me send through my ColdSend IPs from a different front-end?”
Partially yes — but only for sending.
The API will expose an HTTP endpoint that accepts payloads from external CRMs or custom code and dispatches mail through your pre-warmed ColdSend IP/domain. It will not expose SMTP relay, so traditional “cold-email tools” that insist on SMTP credentials still won’t connect.
You (or a developer) will need to write a small bridge that pushes contacts and copy to the ColdSend API; the mail itself will always leave our infrastructure.
Bottom line
Today: ColdSend infrastructure is usable only inside ColdSend.
Post-API: you can programmatically inject mail into ColdSend, but you still can’t plug us into another tool’s SMTP screen.