This estimator calculates mailbox numbers based on recommended delivery constraints: maximum 3 mailboxes per domain, 50 daily cold emails per mailbox, and balanced sending mixes.
Google
Microsoft
CMSEstimated annual savings vs Google Workspace: $2,033
Estimates are directional and based on public seat pricing assumptions ($8.40/mailbox for Google Workspace and $7.20/mailbox for Microsoft 365).
Yes! We offer a free 7-day trial on all plans. Free trial accounts have a 30 emails/day limit during the trial period. Full volume unlocks on your paid subscription, subject to good sending patterns and our network protection limits.
Stated daily limits (up to 1,500/day, 5,000/day, 15,000/day) represent the maximum unlockable sending capacity for your plan. To protect our network infrastructure and prevent spam and abuse, all new accounts start with conservative daily volume. We automatically increase your limit in stages as you establish clean sending patterns and maintain healthy metrics (low bounce rates and compliant recipient lists).
Yes. Every plan includes unlimited mailboxes and unlimited domains. We never charge per mailbox like Google Workspace or Microsoft 365. Pricing is based on dedicated infrastructure capacity and maximum daily sending volume.
Yes. Every customer gets their own dedicated, isolated mail server infrastructure and IPs. Your sending reputation, IP addresses, and deliverability metrics are completely separated from every other sender on the platform.
The Unibox aggregates all inbound replies across all your mailboxes and domains into a single unified inbox. Instead of logging into dozens of separate inboxes, your sales team manages all conversations from one fast feed.
No. Cold Mail Server is purpose-built for outbound B2B cold email. As long as you comply with standard anti-spam hygiene (clean recipient lists, low bounce rates, and unsubscribe links), we will never disable your account for sending cold outreach.
Google and Microsoft are general-purpose email providers that regularly disable accounts used for cold email and charge $7–$8/mailbox/mo. Cold Mail Server provides dedicated outbound infrastructure with unlimited mailboxes at a flat, predictable monthly rate.
We actively monitor outbound health to keep our network clean. If your account experiences high bounce rates (over 5%) or spam complaints, our system temporarily holds your sending volume at a safe level to protect your domains and our network until you verify your recipient list.
Yes! Cold Mail Server uses a Zero-DNS-Update setup. Your domains configure our central SPF and MX records once, allowing infrastructure scaling and IP management behind the scenes without needing any DNS modifications on your domains.