Maildoso vs Mission Inbox (2026): which should you pick?

Pick Maildoso if

• Fits if you need 30 or more mailboxes for an outbound team
• Works for senders who already run Instantly or Smartlead

Look elsewhere if

• Skip it if you need just a few mailboxes, since 30 is the smallest block
• Not for you if you want a trial or a discount, because neither exists
• Watch out: domains cost extra, $15 a year or $11.90 a month pre-warmed
• Tight if you want volume per mailbox: 15 cold emails a day each

Pick Mission Inbox if

• Fits if you want dedicated IPs for outbound and already own a sequencer
• Works for agencies that keep each client's sending apart

Look elsewhere if

• Not for you if you want to write or schedule campaigns, because there is no sequencer
• Tight if you send past 5,000 a month, since Lite pauses at the limit, counts warm-up emails and has no overage billing
• Skip it if you want a trial, as none is offered
• Pricey if you add warm-up, which is a paid add-on, or move to Scale at $199 a month

Maildoso

• Each mailbox sends at most 15 cold emails and 80 warm-up emails a day, and new mailboxes still need about 14 days of warm-up unless they sit on pre-warmed domains.
• Domains are not included in monthly plans: registration is $15 a year and a pre-warmed domain is $11.90 a month.
• Quarterly plans with domains included are labeled legacy on the pricing page; the monthly blocks are the current plans.
• Subscriptions are canceled through support chat or email, and the page says it has a no-discount policy with no promotions.

Mission Inbox

• It is infrastructure only: there is no sequencer, so you need another tool to write and schedule campaigns.
• Lite is a fixed plan with no overage billing; at 5,000 sends, counting warmup emails, you have to move to Scale.
• Premium Warmups are a paid add-on, and sends include warmup emails.
• Pricing is a monthly rate; the calculator shows prepaid-monthly (10% off) and annual (17% off) options.

Maildoso

Mailboxes built for outbound

Dedicated mailboxes on the vendor's own servers and IPs, with IP rotation and automatic replacement of IPs that stop working.

Automatic DNS setup

SPF, DKIM and DMARC records are configured when you register mailboxes under a domain bought or connected through the dashboard.

Self-healing and health scores

Burned-out mailboxes are disconnected from campaigns for 14 days, and inbox placement tests run every 3 days with a health score per mailbox.

Sequencer export

Mailboxes can be exported to outreach platforms; Instantly, Smartlead and EmailBizon sync with one click, and the vendor says 9 sequencers are supported.

API and MCP server

Register domains, create mailboxes and push them to a sequencer from code or from an AI assistant such as Claude.

Pre-warmed domains

Domains warmed in advance, each holding up to 50 mailboxes, so new mailboxes can start sending without the usual 14-day wait.

Mission Inbox

Dedicated IP addresses

Each mailbox sends from IP addresses reserved for the account instead of a shared pool, so other senders' habits do not affect its reputation.

MI Shield pre-send scan

The vendor's own AI checks content, headers and DNS before each outbound send to catch problems before a campaign goes live.

Automatic DNS and mailbox setup

Mailboxes are created in one step and DNS records are configured automatically, so they can be connected to a sequencer afterwards.

Cubes for separating clients

Cubes split clients, brands and campaign workloads into separate sending environments, which matters for agencies.

Premium warmup add-on

Mailbox warmup is a paid add-on, billed in credits per mailbox. You can instead warm up with your own tool or skip warmup.

API and SMTP access

An API and SMTP sending give campaign or product email traffic its own sending reputation, with documentation linked from the site.

Maildoso

• 30 mailboxes$75

  per month for 30 mailboxes ($2.50 each)

  Aimed at early-stage teams. Up to 15 cold emails a day per mailbox, plus the features every plan includes.

• 300 mailboxes$225

  per month for 300 mailboxes ($0.75 each)

  Aimed at expanding teams. Same features and 15-a-day limit per mailbox as the smaller block.

• 1,000 mailboxes$499

  per month for 1,000 mailboxes ($0.49 each)

  Aimed at large-scale campaigns. Same features and per-mailbox limit.

Mission Inbox

• Lite$50

  per month for 15 mailboxes and 5,000 sends

  Dedicated IP addresses, MI Shield protection, analytics and sending logs. A fixed plan: it pauses at the send limit until you move to Scale.

• Scale$199

  per month for 30 mailboxes and 10,000 sends

  Aimed at agencies and companies sending for clients. Dedicated IPs, MI Shield, analytics and logs; more mailboxes and sends can be added.

Maildoso

No public discounts listed.

Mission Inbox

• Annual discount

  17% off with annual billing

  The pricing page calculator lists an annual option at 17% off and a prepaid monthly option at 10% off, against pay-as-you-go monthly.