ImprovMX forwards mail on your domain to a mailbox you already read. MCPmailer is the mailbox an agent holds the conversation in.
Forwarding and aliases · ImprovMX claims checked July 2026
ImprovMX forwards mail addressed to your domain into a mailbox you already have, free for basic use, with paid plans from a few dollars a month and a small SMTP add-on if you also need to send. It is simple, fast, and does exactly one thing.
If you want support@yourdomain.com to land in an inbox you already read, ImprovMX is the cheapest and least fussy way to do it. For a solo founder or a small alias set, it is the right tool.
Forwarding is a delivery mechanism, not a mailbox. Nothing is stored, so there is nothing to search, no thread to continue, and no history for the agent to read. Add a send path and you own DKIM alignment, bounces, and suppression too.
A forwarder passes the message on and forgets it. An agent that needs to know what it told this person in March has to have kept the mail somewhere, which is exactly what the mailbox, the thread model, and search_inbox are for.
Forwarded mail is often modified in transit, which invalidates the original DKIM signature and can fail DMARC alignment with it. Mail delivered to its own mailbox on your verified subdomain has no intermediate hop to break.
The SMTP add-on lets you send, and then bounce handling, complaint feedback, suppression, and reply-first quotas are yours. Those are the controls that keep a sending domain alive once an agent is choosing recipients.
Every row is a claim we could defend with their documentation open beside it. Where they are ahead, the row says so.
Be honest about which of these describes your case.
An alias a human reads
Forwarding is correct and nearly free. Nothing here improves on it.
An agent that must reply in thread
It needs stored mail and a thread model, which a forwarder does not have.
Both, briefly
Forward a legacy alias into an agent address while you cut over, then drop the forward.
You can give it an address that forwards somewhere. The agent still needs a mailbox to read from, a way to send, and somewhere the thread lives.
It can. Forwarding often modifies the message and breaks the original DKIM signature, and once DKIM fails DMARC alignment can fail with it.
Yes, and it should be: forwarding stores nothing, and most of what you are paying us for is what happens after the mail arrives.
Yes, and it is a good way to migrate. Keep the forward until in-flight threads dry up, then remove it.
Forwarding is the cheapest way to receive at an address you own, and it is a delivery mechanism rather than a mailbox. When the agent needs to hold the conversation rather than pass it along, that is this.
The free tier is 3,000 emails a month across three agent inboxes, no card, with receiving, threading, and search included. Enough to watch a real conversation happen before you decide.
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