On this page
vsInboxKit vs AeroSend: Real Accounts and InfraGuard vs Private SMTP Isolation (2026)
InboxKit and AeroSend are both cold-email-specific and both lead with deliverability monitoring. The difference is what sits underneath. InboxKit gives you real Google Workspace, Microsoft 365 and Azure accounts plus InfraGuard auto-pause. AeroSend gives you private SMTP infrastructure on dedicated, aged IPs, managed warmup, and its own domain burn detection, sold in batches of 30 inboxes with a bring-your-own-domain model.
AeroSend homepage as of May 2026
Our Summary
AeroSend (aerosend.io) is deliverability-first cold email infrastructure built around isolation. It does not sell Google or Microsoft seats. Instead it provisions private infrastructure with dedicated, aged IPs, automated SPF, DKIM and DMARC, and mailboxes you plug into Smartlead, Instantly, lemlist, Woodpecker, Reply.io or Saleshandy. You bring your own .com domains from any registrar and AeroSend handles all DNS configuration and warmup.
AeroSend's second pillar is monitoring. It runs a 5-metric burn-detection algorithm, domain health scoring from 0 to 100, biweekly inbox placement tests, proactive IP rotation, and 24/7 automated monitoring, with a deliverability guarantee that refunds your costs if it does not outperform your current setup. The company reports 2,000+ active accounts, 150+ agencies, and zero mass bans in its history, plus 1:1 access to founder Namit, a Smartlead Hall of Famer.
Inboxes are sold in batches of 30 with a 30-inbox minimum. The first 150 inboxes are $4 each per month, dropping to $2 for every inbox after 150. From purchase to full sending capacity takes about three weeks (24 to 48 hours for domain provisioning plus a 21-day managed warmup).
Feature Comparison
| Feature |  InboxKit | |
|---|---|---|
| Infrastructure | ||
| Account Type | Real Google, Microsoft 365 & Azure | Private SMTP infrastructure |
| IP Addresses | Dedicated US IPs | Dedicated, aged IPs with rotation |
| Domains | Handled for you | Bring your own |
| Pricing & Minimums | ||
| Starting Price | $2.50 to $3.50/mailbox | $4/inbox ($2 above 150) |
| Minimum Purchase | 10 mailboxes | 30 inboxes (batches of 30) |
| Monitoring & Deliverability | ||
| Monitoring | InfraGuard with auto-pause | 5-metric burn detection (alert-and-act) |
| Warmup | Isolated warmup add-on ($3/mb/mo) | Managed 21-day warmup included |
| Placement Tests | Unlimited | Biweekly |
| Setup & Integrations | ||
| Setup Time | Under 60 seconds | About 3 weeks |
| Sequencer Integrations | 24+ native | 6 listed (IMAP/SMTP) |
| Free Trial | Self-serve start | None (deliverability guarantee) |
Switch to InboxKit
Dedicated IPs. Isolated infrastructure. From $2.50/mo.
Pricing Comparison
InboxKit
inboxkit.com
- Google WorkspaceFrom $2.50/mailbox/mo
Real US-IP Google accounts, full admin access. Plans: Professional $31/mo (10 slots), Agency $81/mo (30 slots), Enterprise $250/mo (100 slots, $2.50/extra on Enterprise annual)
- Microsoft 365From $2.50/mailbox/mo
Official Microsoft 365 accounts with admin control. Same plan tiers as Google Workspace, no Microsoft premium.
- Azure Mailboxes$30/domain
Up to 100 mailboxes per domain on Azure infrastructure
AeroSend
aerosend.io
- First 150 inboxes$4/inbox/mo
Minimum 30 inboxes, sold in batches of 30. Includes dedicated IPs, managed warmup, and biweekly placement tests.
- Every inbox after 150$2/inbox/mo
Volume discount applies automatically. Example: 300 inboxes costs (150 x $4) + (150 x $2) = $900/mo.
- DomainsBring your own
AeroSend does not provide domains. Buy .com domains from any registrar (about $10 to $12 per year) and connect them.
Pricing Verdict: AeroSend starts at $4/inbox for your first 150 inboxes (a $120 batch of 30), dropping to $2 above 150, with no annual discount and a 30-inbox minimum. InboxKit runs about $2.50 to $3.50 per mailbox, starts at 10 mailboxes, and includes monitoring. InboxKit is generally cheaper and lets you start smaller with real provider accounts. AeroSend costs more at low volume and requires a 30-inbox commitment, but you are buying genuine private-infrastructure isolation that real accounts on shared provider pools do not replicate.
Infrastructure and Deliverability
Real Provider Accounts
InboxKit provisions real Google Workspace, Microsoft 365 and Azure accounts with full admin access. AeroSend sells private SMTP infrastructure, so if your campaigns need to send from genuine Workspace or 365 inboxes, InboxKit is the only side of this comparison that delivers that.
Lower Entry Point
InboxKit starts at 10 mailboxes with transparent per-mailbox pricing. AeroSend requires a 30-inbox minimum sold in batches of 30, so the smallest order is $120/mo.
InfraGuard Auto-Pause
InfraGuard does not just alert, it automatically pauses a mailbox when metrics go red, containing a burning domain with no human in the loop. AeroSend's burn detection warns you, but acting on the alert is still up to you or its team.
Azure Option and Transparent Pricing
InboxKit adds Azure ($30/tenant for up to 100 mailboxes) and lists every price publicly. AeroSend has no Azure tier and no annual discount.
InboxKit dashboard — 18M+ emails, 5,039 domains, 16,754 mailboxes for a single client
AeroSend homepage
Pros & Cons
InboxKitStrengths
- Real Google, Microsoft 365 and Azure accounts with full admin access
- Starts at 10 mailboxes with transparent per-mailbox pricing
- InfraGuard auto-pause contains a burning domain automatically
- Domains and DNS handled, live in under 60 seconds
Limitations
- Isolated Warmup is a paid add-on ($3/mailbox/mo)
- No private SMTP isolation-pod model
Strengths
- Private SMTP infrastructure on dedicated, aged IPs
- Monitoring-led: 5-metric burn detection, biweekly placement tests, 0 to 100 health score
- Managed 21-day warmup included plus a deliverability guarantee
- Founder-led expert access (Smartlead Hall of Famer)
Limitations
- No Google or Microsoft provider accounts (private SMTP only)
- 30-inbox minimum, sold in batches of 30
- Bring your own .com domains
- About 3 weeks to full sending capacity; no free trial
Who Should Choose What
AeroSend is a credible, monitoring-led choice if you specifically want private SMTP infrastructure with dedicated, aged IPs and per-batch isolation, and you are comfortable with a 30-inbox minimum, a bring-your-own-domain model, and a three-week ramp. InboxKit wins for teams that want real Google, Microsoft and Azure accounts, a 10-mailbox entry point, transparent pricing, and InfraGuard's automated auto-pause. Both are strong; the deciding factor is account type and how much infrastructure isolation you actually need.
Got questions? We've got answers.
No. AeroSend provisions private SMTP infrastructure on dedicated, aged IPs. InboxKit is the option if you need real Google Workspace, Microsoft 365, or Azure accounts with full admin access.
AeroSend has a 30-inbox minimum, sold in batches of 30. The first 150 inboxes are $4 each (a batch of 30 is $120/mo), then $2 each above 150. InboxKit starts at 10 mailboxes on the Professional plan.
Both are strong. AeroSend runs a 5-metric burn-detection algorithm with biweekly placement tests and 0 to 100 domain health scoring. InboxKit's InfraGuard adds automatic auto-pause, so a burning domain is contained without manual intervention.
No. AeroSend is bring-your-own-domain: you buy .com domains from any registrar and AeroSend configures DNS and warmup. InboxKit handles domains and DNS for you.
InboxKit is generally cheaper at low volume (about $2.50 to $3.50/mailbox, starting at 10 mailboxes) and includes monitoring. AeroSend is $4/inbox for the first 150 (dropping to $2 above 150) with a 30-inbox minimum, but includes private-infrastructure isolation and managed warmup.
Keep Reading
Ready to try InboxKit?
Dedicated US IPs. Isolated infrastructure. Real Google & Microsoft accounts from $2.50/mo.