Line by line
| Feature | Inboxkit | Smartlead |
|---|---|---|
| Mailboxes | Official, paid Google Workspace and Microsoft 365, plus Azure | Google, Outlook and SMTP from third-party vendors |
| Claude Code / Codex (MCP) | Remote MCP server, connects to Claude Code and Codex | Smartlead offers an MCP server |
| Google price | $3 a mailbox, or $2.50 on annual billing | $4.50 a mailbox, plus $13 a domain a year |
| Microsoft price | $3 a mailbox; Azure $30 a tenant for up to 100 | Outlook $4.50 or $5 a mailbox, plus $13 or $16 a domain a year |
| Where they work | One-click export to 24+ sequencers, Smartlead included | Cannot be transferred or used outside Smartlead |
| Billing | Pay only for the mailboxes you add | Mailboxes monthly; domains yearly on a fixed 12-month term |
| API | Full REST API with webhooks on every account, 119 endpoints | API and webhooks from Pro at $94 a month |
| Warmup (add-on) | 14 days on an isolated network, $3 a mailbox | Included in Smartlead plans; SmartSenders sets it up |
| Placement tests (add-on) | Unlimited with InfraGuard, which checks every six hours with auto-pause | SmartDelivery add-on, from $49 a month |
Competitor details from public pages, checked 28 Oct 2026. Sources: Smartlead SmartSenders (smartlead.ai); Smartlead pricing (smartlead.ai); Smartlead pricing (text version) (smartlead.ai); SmartSenders FAQs (helpcenter.smartlead.ai); Inboxkit pricing.
Competitor offers can change after that date. Trademarks belong to their owners.
Prices at common volumes
| Mailboxes | Inboxkit, monthly | Inboxkit, annual | Smartlead |
|---|---|---|---|
| 100mailboxesGoogle mailboxes | Inboxkit, monthly$300 | Inboxkit, annual$250 | Smartlead$450 |
| 500mailboxesGoogle mailboxes | Inboxkit, monthly$1,500 | Inboxkit, annual$1,250 | Smartlead$2,250 |
| 1,000mailboxesGoogle mailboxes | Inboxkit, monthly$3,000 | Inboxkit, annual$2,500 | Smartlead$4,500 |
Every Smartlead plan includes warmup, and SmartSenders sets it up for you. Ours is a $3 add-on.
Mailboxes only. SmartSenders adds $13 a domain a year for Google. Sending from Smartlead needs a Smartlead plan with either option.
SmartSenders pricing against Inboxkit
SmartSenders charges per mailbox each month and per domain each year. Fresh Google mailboxes are $4.50 a month, plus $13 a domain. Outlook is $4.50 or $5, plus $13 or $16 a domain. Pre-warmed mailboxes are $9, plus $18.
Inboxkit is $3 a mailbox on monthly billing, or $2.50 on annual, for Google or Microsoft. Sending from Smartlead needs a Smartlead plan either way, from $39 a month.
At 1,000 Google mailboxes on monthly billing, SmartSenders costs $4,500 a month before domain fees. Inboxkit costs $3,000 at today’s published rate.
SmartSenders mailboxes: Google, Outlook and SMTP
SmartSenders sells Google, Outlook and SMTP mailboxes inside Smartlead. They come from third-party providers such as Zapmail, InfraInbox and Mailreef. Its pricing page also lists a Google option with admin access, at $4.50.
Inboxkit sells official, paid Google Workspace and Microsoft 365 mailboxes at the same $3 price. Microsoft volume can run on Azure, where one tenant holds up to 100 mailboxes for $30 a month. Pre-warmed mailboxes are live in hours.
SmartSenders setup, domains and moving mailboxes
SmartSenders sets up the domains, DNS, SPF, DKIM and warmup for you. Smartlead’s help center says its domains and mailboxes cannot be transferred or used outside Smartlead. Domains are billed yearly, and mailboxes monthly.
Inboxkit mailboxes export in one click to 24+ sequencers, Smartlead and Instantly included. You buy domains or connect your own, and SPF, DKIM and DMARC are configured for you. Orders complete in 30 to 120 minutes.
SmartSenders warmup and inbox placement tests
Every Smartlead plan includes warmup, and SmartSenders handles the warmup setup. Inbox placement testing is SmartDelivery, an add-on from $49 a month.
Inboxkit’s warmup is an add-on at $3 a mailbox and runs for 14 days on an isolated network. InfraGuard, also an add-on, checks blacklists, DNS, bounces and inbox placement every six hours. It has alerts and auto-pause, and includes unlimited placement tests. Its first month is free.
SmartSenders API, MCP and automation
Smartlead’s API and webhooks start on its Pro plan, $94 a month. Smartlead also offers an MCP server.
Every Inboxkit account gets the full REST API, with 119 endpoints and webhooks. Connect Claude Code or Codex to Inboxkit’s remote MCP server to run your mailbox work from an agent.
Support and team access
Inboxkit is rated 4.7 out of 5 on G2 from 120 reviews. G2 named it a High Performer for Spring 2026.
Inboxkit support runs 24/7 on Slack, in-app chat and email. Every account gets unlimited team members and workspaces.
Move your sending mailboxes to Inboxkit
Create a free account
Pay only for the mailboxes you add. No plan to pick first.
Buy or connect domains
Then add Google Workspace, Microsoft 365 or Azure mailboxes on them.
Export to your sequencer
One click to 24+ sequencers, including Smartlead and Instantly.
Run both side by side
Keep Smartlead running while the new mailboxes warm up.
Questions about Smartlead
Do Inboxkit mailboxes work with Smartlead?
Yes. Export them to Smartlead in one click. The same mailboxes also export to any of 24+ sequencers, so you can move them later.
How does SmartSenders pricing work?
You pay per mailbox each month and per domain each year. Fresh Google mailboxes are $4.50 plus $13 a domain. You also need a Smartlead plan, from $39 a month.
Is Inboxkit cheaper than SmartSenders?
For Google mailboxes, yes: $3 here against $4.50, before domain fees. At 1,000 mailboxes that is $3,000 a month against $4,500. Smartlead plans include warmup, which is a $3 add-on here.
Can I use SmartSenders mailboxes outside Smartlead?
Smartlead’s help center says domains and mailboxes bought through SmartSenders cannot be transferred or used outside Smartlead. Inboxkit mailboxes export to any of 24+ sequencers.
Do I still need a Smartlead plan?
To send from Smartlead, yes, with either option. Smartlead plans start at $39 a month on Base, and every plan includes warmup.
How do I move from SmartSenders to Inboxkit?
Open a free account, buy or connect domains, and add mailboxes. Export them to Smartlead in one click. Keep your SmartSenders mailboxes sending until your campaigns have moved.
Open a free account
$3 a mailbox, no minimum. Google Workspace, Microsoft 365 and Azure.
