CheapInboxes built its name on bulk Google Workspace at low cost with 24/7 support. But its tiered pricing only beats flat $2.50 above 1,000 mailboxes — and it ships with zero monitoring.
| Feature | CLAYINBOX | CheapInboxes |
|---|---|---|
| Pricing model | Flat $2.50, any volume | Tiered: $3.50 (1–99) → $2.80 (1,000+) |
| Platform fee | $0 | $0 |
| Google Workspace | ✓ full admin | ✓ Business Starter, full admin |
| Microsoft 365 | ✓ | ✓ |
| Azure high-density | ✓ | ✗ |
| Dedicated IMAP/SMTP | ✓ | ✗ |
| Pre-warmed | ✓ +$2 | ✓ included claim, same-day delivery |
| Sequencer connection | One-click export + OAuth | OAuth auto-connect + auto-reconnect (strong) |
| Warmup | Included, isolated | Pre-warmed model; ongoing warmup external |
| Free replacements | ✓ unlimited | Not advertised |
| Unified inbox | ✓ | ✗ |
| Blacklist / DNS monitoring | ✓ included | ✗ |
| Placement tests | ✓ unlimited | ✗ |
| Domain isolation | ✓ | ✓ one domain per workspace |
| API | 70+ endpoints + MCP | 70+ endpoints, webhooks, MCP |
| Support | Live chat | 24/7, strong reputation |
| Whitelabel | ✓ | ✗ |
Break-even vs CLAYINBOX: never below 1,000 boxes; at 1,000+ their $2.80 still trails $2.50.
Operational polish on delivery — same-day pre-warmed accounts, OAuth auto-connect (no app-password copy-paste), auto-reconnect when sequencer links drop, and a support reputation that's arguably the best in the budget tier. Their developer API with 70+ endpoints and MCP support is also unusually complete for a "cheap" provider.
Price at every realistic volume — their lowest tier ($2.80 at 1,000+) never reaches flat $2.50. Beyond price: monitoring, placement tests, weekly reports, unified inbox, Azure density, SMTP option, whitelabel. CheapInboxes hands you credentials and walks away; CLAYINBOX keeps watching the infrastructure after delivery.
Both use one-domain-per-workspace isolation, so the mental model transfers directly. Reconnect domains, bulk-provision, OAuth into your sequencer. Their month-to-month billing (7-day notice) means no contract friction.
Flat $2.50/mailbox. Warmup, monitoring, replacements, unified inbox — all included.