Sendbox
Our pickBest for: teams whose top priority is dedicated IPs and deliverability
If deliverability is what you're optimizing for, Sendbox is the pick we'd point you to first. Every plan, not just the top one, ships with dedicated IPs, a structural difference from Instantly, since your sending infrastructure is isolated per customer so nobody else's reputation problems become yours. That isolation is the whole reason Sendbox exists: it was built to answer the shared-infrastructure issue most cold email platforms never solve.
Warmup that actually clears detection filters, validation, inbox placement testing, blacklist monitoring, and a built-in dialer all come standard, with nothing sold as a bolt-on. The entry-level Essential plan includes 75,000 emails a month and 30,000 leads, against Instantly's $47/mo Growth plan, which tops out at 5,000 emails and 1,000 contacts on shared infrastructure.
Strengths6
- Every plan ships with dedicated IPs, including the entry tier
- Sending infrastructure is isolated per customer, so other users' problems can't touch your reputation
- Warmup, validation, placement testing, and blacklist monitoring all come bundled in
- A dialer is built in for phone follow-up
- Webhooks ship with HMAC signature verification
- 75,000 emails a month included on the entry plan
Limitations3
- Costs more to get started than Instantly's Growth plan
- Fewer community resources and playbooks than the more established Instantly
- Still building out its ecosystem of templates and third-party guides
PricingFour tiers, Essential, Plus, Pro (with white-label), and Agency, each a flat monthly rate with no metered add-ons.
Best forTeams for whom deliverability and infrastructure isolation are non-negotiable.






