Head to head

InboxKit vs Premium Inboxes

Same facts, side by side: starting price, free tier, MCP, API and what each one is actually built for.

InboxKit

$2.50/mailbox/mo

Google Workspace and Microsoft 365 mailboxes from $2.50 per mailbox per month on yearly wallet billing. REST API included.

Where InboxKit fits

  • Agencies that want Google and Microsoft at the same rate
  • Teams billing mailboxes from a wallet with no minimum
  • Senders connecting Instantly, SmartLead, or Lemlist
  • Shops that need REST API and webhooks

Done-for-you Google Workspace and Microsoft 365 inboxes for outbound sending, from $3.50 per inbox per month.

Where Premium Inboxes fits

  • Outbound recruiting teams that need real Workspace or M365 boxes
  • Agencies standing up client domains
  • Desks that want DNS and warmup handled
  • Buyers who need a public API on every plan

At a glance

DetailInboxKitPremium Inboxes
Starting price$2.50/mailbox/mo$3.50/mo
Free tier–No–No
MCP server–No–No
Public API✓Yes–No
Listed underDeliverabilityDeliverability

Where they pull apart

InboxKit

Stands out: Same $2.50 yearly rate for Google and Microsoft, with no slot minimum on wallet billing.

Watch out: The $2.50 figure is yearly Enterprise wallet billing. Warmup is $3 per mailbox extra. A FAQ still cites a $39 Professional pack.

Not the right fit for

  • Buyers who want warmup in the $2.50 rate
  • Teams that need a traditional free trial

Premium Inboxes

Stands out: Official Workspace and M365 inboxes with free replacements and sub-six-hour setup.

Watch out: It supplies the inboxes only. You still need a sequencer to send, and there is no MCP.

Not the right fit for

  • Teams that only need a sequencer, not inboxes
  • Buyers who want MCP

Pros and cons

InboxKit

  • $2.50/mailbox/mo yearly, no minimum
  • Google and Microsoft same price
  • REST API and webhooks included
  • Warmup is $3/mailbox extra
  • No traditional free trial
  • FAQ still cites a $39 pack

Premium Inboxes

  • Official Workspace and M365, not lookalike domains
  • Setup in under six hours
  • Public API on all plans
  • No MCP
  • You still need a sequencer to send

What each one costs

InboxKit

$2.50/mailbox/mo

Google and Microsoft mailboxes $2.50/mailbox/month on yearly wallet billing, no minimum. Azure tenants $30/tenant/month. Warmup add-on $3/mailbox/month. FAQ also cites Professional from $39/month for 10 mailboxes; the printed wallet cards are $2.50. API included. No traditional free trial. Confirm current terms on the vendor site.

Checked 19 Sep 2026

Premium Inboxes

$3.50/mo

From $3.50/inbox/mo. Confirm current pricing on the vendor site.

Checked 7 Sep 2026

Common questions

Is InboxKit cheaper than Premium Inboxes?
InboxKit starts lower, at $2.50/mailbox/mo against $3.50/mo for Premium Inboxes. That is the entry plan on each side, so the real number depends on seats and the tier you land on.
Can you try InboxKit or Premium Inboxes for free?
Neither carries a free tier on our listing.

Not the pair you wanted?

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Editorial listings, never paid rankings. Prices checked 19 Sep 2026. Confirm current terms on the vendor site. Spot an error?