Cold email infrastructure built for agencies
Run campaigns for multiple clients on dedicated IPs with fully isolated infrastructure. White-label branding is available starting on the Pro plan, and every client keeps a sending reputation that never bleeds into anyone else's.
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Add more clients without adding more risk
Every client sends from an IP that belongs only to them, with no shared pool and no cross-client reputation risk.
Custom branding on reports and dashboards is available starting on the Pro plan, and the Agency plan adds a dedicated account manager on top.
Connect as many mailboxes per client as the work calls for, with no per-seat charges attached.
Warmup, validation, inbox placement testing, and blacklist monitoring all ship standard, on every plan.
The way agencies put Sendbox to work
Spin up a dedicated workspace for each client, connect their mailboxes, bring leads in through CSV import, and set your sending schedule. Every workspace runs on its own dedicated IP from the start.
Each client's campaigns run on infrastructure that's isolated from every other client's. A deliverability problem on one account stays contained there, with no shared IP pools and no risk of it spilling over.
Custom branding on reports and dashboards is available from the Pro plan onward. Step up to the Agency plan and you also get a dedicated account manager plus 2.5M emails a month.
Run campaigns for 10, 50, or well over 100 clients at once. Because every workspace gets its own dedicated IP, one problem client can never burn another client's domain reputation.
Run SDR teams across several client accounts from one place. A unified inbox, AI reply tagging, and per-campaign analytics make client-by-client reporting possible without jumping between tools.
Bring the built-in dialer, CRM, and sequencing together in one platform for every engagement. Webhook integrations handle pushing data into your client's CRM automatically.
What pulls agencies over to Sendbox
Your clients deserve dedicated IPs, not a shared pool
Most tools built for agencies still put every client on shared infrastructure, so one client's spam complaint drags down deliverability for the rest. Sendbox isolates each workspace behind its own dedicated IP, keeping every client's reputation entirely independent of the others.
White-label built for agency workflows
The Pro plan includes white-label branding across reports and dashboards, and the Agency plan layers on custom branded reports, a dedicated account manager, and 2.5M emails a month. Saleshandy offers white-label starting at $139/mo, but on shared infrastructure rather than dedicated.
Per-client isolation, not just per-client workspaces
Plenty of tools give you separate workspaces per client while still running them on shared infrastructure underneath. Sendbox takes it a step further and gives each workspace its own dedicated IPs, so if client A gets blacklisted, client B never even notices.
Got questions? We've got answers.
Still stuck? Talk to us →White-label branding starts on the Pro plan, which includes 500,000 emails and unlimited leads. Moving up to the Agency plan adds 2.5M emails, custom branded reports, and a dedicated account manager.
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