InboxKit
InboxKit is the leading cold email infrastructure platform that automates domain and mailbox provisioning at scale. We help cold email agencies, sales teams, and outbound consultancies set up Google Workspace and Microsoft 365 mailboxes in minutes, not hours. Key features include automated DNS configuration, one-click export to 15+ sequencers (Instantly, SmartLead, Lemlist, Reply.io, etc.), real-time deliverability monitoring, and bulk mailbox management. As an official Google Cloud Partner and Microsoft Partner, we provide enterprise-grade infrastructure without the manual setup overhead.
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PureMail
4.8 out of 5 stars
(45 Ratings)
PureMail provides managed Google Workspace and Microsoft 365 email inboxes for teams running cold-email outreach. Customers supply their own domains and select an inbox volume; PureMail provisions mailboxes, configures SPF, DKIM, DMARC and MX records, and connects accounts to sending platforms such as Instantly, Smartlead, Lemlist and other sequencers. Plans are billed monthly per inbox, with volume-based rates, DNS setup and integration included and no setup fee. Accounts include mobile and web access, while support is available through dashboard tickets. PureMail is intended for lead-generation agencies, B2B sales teams, SDRs, founders and other outbound teams that need multiple business email inboxes. The company also publishes a cold-email tool directory with provider pricing, sending limits and rubric scores.
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Terlido
Terlido is a cloud-based platform for teams running cold-email campaigns from connected Gmail, Microsoft 365, or SMTP/IMAP mailboxes. Warmup and campaigns share one daily per-mailbox send budget, with recipient-domain throttling, suppression controls, and automatic pauses at bounce or spam thresholds. Before sending, it checks SPF, DKIM, DMARC, and MX records; unsubscribe headers remain on. Sequences combine email, WhatsApp, LinkedIn, and call steps. LinkedIn steps become prepared tasks for a person, not automated account actions. Terlido Newsletter is free for up to 10,000 subscribers. The platform also offers a unified inbox, contact management, campaign analytics, two-way HubSpot sync, and a REST API and MCP server on eligible plans; agent use follows sending limits and workspace controls. Teams can manage outreach campaigns and replies from one workspace.
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Ballast
Ballast is a cold email platform for teams running one-to-one outbound campaigns from their own mailboxes. Users can connect Google Workspace, Gmail, Microsoft 365, or other SMTP/IMAP accounts; import leads; build multistep sequences with personalization and variants; and manage replies in a shared inbox. The platform includes mailbox warmup, sending schedules, domain checks, inbox-placement tests, bounce thresholds that can pause sending, and campaign analytics. Plans are priced by monthly email volume and include unlimited mailboxes and seats, API access, webhooks, and MCP tools. Teams can connect AI models for reply classification and drafting, configure Slack reply alerts, or automate workflows through n8n. CSV presets support lead imports from Apollo, Clay, Instantly, Smartlead, and Lemlist.
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