How is Combo (SMTP + Google Workspace) different from pure SMTP on Maildoso?

Combo mailboxes route through Google Workspace, so the underlying delivery path uses Google's MX infrastructure. Pure SMTP routes through Maildoso's own sending fabric. The Combo premium ($2-$3 vs $1.90-$2.50) reflects the real Google Workspace license layer. Combo typically delivers 5-15 percent better to Google-recipient lists; the differential narrows on Microsoft-heavy lists.

Does Maildoso's 400K-mailbox track record actually matter at smaller scale?

Less so for small fleets, more so for fleets above 200 mailboxes. The operational failure modes Maildoso has engineered around (DNS propagation at scale, IP pool stability, capacity continuity) only surface above a certain threshold. A 50-mailbox fleet on Maildoso experiences the platform similarly to a 50-mailbox fleet on a newer provider; a 1,000-mailbox fleet experiences the track record difference directly.

What does Maildoso's shared IP pool mean for buyer-level deliverability?

Your reputation is influenced by the behavior of other senders sharing your IP pool. Maildoso's scale and 4.7 G2 rating suggest the pool composition is well-managed at the provider level, but there is no public mechanism to query your specific pool before provisioning. For high-volume senders with strict deliverability requirements, this is the case for a provider with dedicated IPs (Infraforge) over shared SMTP at any rate.

How much does the API and MCP support actually save at scale?

At 500-mailbox provisioning, the difference between API-driven setup and manual panel-clicking is roughly 20-40 operator hours. At $80-$150 per operator hour, the savings range from $1,600 to $6,000 just on initial provisioning, recurring partially every month thereafter. This is the line item that does not appear on the pricing page but determines real-world cost economics for large fleets.

Do I need to add domain costs separately when modeling Maildoso bills?

Yes. Mailbox prices ($1.90-$3) are mailbox-only. Domains are $2 each and are not bundled. A typical cold email fleet runs one domain per 5-10 mailboxes for reputation diversification, so a 100-mailbox fleet might add $20-$40 in domain fees, a 500-mailbox fleet $100-$200. Domain registration through Maildoso is convenient but not mandatory; bring-your-own-domain is supported.

Maildoso Pricing: What You Pay

Full breakdown of every Maildoso plan, mailbox type, and domain cost. Here is what you actually pay at scale and how it compares to InboxKit.

By Akshay Prasath

6 min readUpdated Mar 2026

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Bottom line

Maildoso is the volume specialist of the email infrastructure category. SMTP mailboxes from $1.90 each, Combo (SMTP + Google Workspace) from $2-$3, and domains from $2. The published rate is the cheapest in the category, and the operational track record (400,000+ mailboxes under management, 10M+ daily sends) backs the pricing with proven scale capacity that newer providers cannot demonstrate.

The deliberate choice is no bundled deliverability tooling: no warmup, no verifier, no placement testing, no blacklist monitor. The product is raw SMTP at a price designed to make 100-500 mailbox fleets economically viable, on the assumption that warmup and monitoring live in the sending platform on top.

Maildoso Plans

Plan	Price	What you get	Watch out for
SMTP Mailboxes per mailbox	$1.90-$2.50/mailbox/mo	SMTP mailboxes Auto DNS configuration One-click integrations (Instantly, Smartlead, Saleshandy) API + MCP support	Shared IP infrastructure No built-in warmup No inbox placement testing No email verifier
Combo (SMTP + GW) per mailbox	$2-$3/mailbox/mo	SMTP plus Google Workspace mailboxes Auto DNS configuration One-click integrations API + MCP support	Shared IP infrastructure Higher cost than SMTP-only tier No built-in warmup or deliverability tools
Domains per domain	From $2/domain	Domain purchase and management Auto DNS records	Price varies by TLD and availability

What's Not Included

The deliverability tooling assumption is the hidden cost

Maildoso's pricing math assumes your sending platform already covers warmup, verifier, placement testing, and blacklist monitoring. For teams running Smartlead, Instantly, or another platform that bundles those tools, the assumption is correct and the raw $1.90 rate is genuinely the floor. For teams running a barebones sequencer or building custom on top of SMTP, sourcing the missing tools standalone costs $75-$200/mo regardless of mailbox count, which erodes the per-mailbox savings versus an all-in provider like InboxKit at $2.50.

$75-$200/mo if not covered by sending platform

SMTP-vs-Combo rate spread doubles at higher Combo volumes

The published SMTP range is $1.90-$2.50 and the Combo range is $2-$3. The spread is not arbitrary: Combo mailboxes pass through Google Workspace, so the underlying license cost is real. A team that wants Google Workspace mailboxes pays roughly 30-60 percent more than pure SMTP. The choice between the two is usually deliverability-driven (Google routes often place better inboxward) rather than cost-driven, but the cost differential is real and compounds across hundreds of mailboxes.

$0.10-$0.60/mailbox premium for Combo over pure SMTP

Domain costs are line-item separate, not bundled

Mailbox prices do not include domains. A typical cold email fleet runs 1 domain per 5-10 mailboxes for reputation diversification, which at scale adds up. A 200-mailbox fleet across 25 domains adds $50 in domain fees on top of the mailbox bill. Maildoso prices domains transparently ($2 each) but does not include them in the per-mailbox rate, so a buyer modeling cost should always add the domain line separately.

$2 per domain, $40-$100/mo at typical fleet sizes

IP pool reputation is shared but not visible to buyers

Maildoso's SMTP fleet shares IP pools across the customer base. The provider claims strong deliverability outcomes and the 4.7 G2 rating supports this at the provider level, but individual customer outcomes depend on which IP pool a buyer lands on. There is no published mechanism to query or audit the IP pool composition before provisioning, which is a real operational consideration at high volume but rarely surfaces on the pricing comparison.

Indirect (potential deliverability variance)

Maildoso bill at typical fleet configurations

Usage scenario	Monthly cost	Notes
50 SMTP mailboxes, 10 domains	$115-$145/mo	50 x $1.90-$2.50 + 10 x $2. Pure SMTP at lower volumes lands in the cheapest configuration in the category, assuming the sending platform handles warmup and monitoring.
100 SMTP mailboxes, 20 domains	$230-$290/mo	100 x $1.90-$2.50 + 20 x $2. The break-point where Maildoso's cost advantage over InboxKit ($250) inverts depends on whether your sending platform covers the deliverability gap.
200 Combo mailboxes, 30 domains	$460-$660/mo	200 x $2-$3 + 30 x $2. Combo (GWS-backed) at this volume is the sweet spot for teams wanting Google routing without paying retail GWS rates of $7/seat.
500 SMTP mailboxes, 75 domains	$1,100-$1,400/mo	500 x $1.90-$2.50 + 75 x $2. This is where Maildoso's scale story actually matters: provisioning, DNS automation, and ongoing fleet management on 500+ mailboxes is operationally heavy, and Maildoso's track record (400K+ mailboxes managed) provides the throughput.
1,000+ mailbox fleet	$1,900-$2,500+/mo	Maildoso's claimed 10M+ daily send capacity is the relevant data point at this scale; the per-mailbox rate amortizes but operational continuity at this volume is the real question, and Maildoso has the longest track record in the category.

The 400K-mailbox track record is the pricing premium that does not show on the page

Maildoso's public pricing is competitive on per-mailbox rate, but the more meaningful pricing story is operational: 400,000+ mailboxes under management and 10M+ daily sends processed. Most infrastructure providers in this category are newer (Mailforge, Infraforge, InboxKit, Zapmail all post-2022) and have not demonstrated continuity at this scale. Maildoso has been running provisioning, DNS automation, and fleet management at a scale where the failure modes have surfaced and been engineered around.

This matters because the failure modes of email infrastructure are not visible until volume reveals them: DNS propagation issues at high mailbox provisioning rates, IP pool degradation under multi-tenant load, MX record drift on dormant domains, capacity bottlenecks during industry-wide sending spikes. Newer providers can match Maildoso's sticker rate but cannot match the operational data on how the platform behaves under sustained 100K-1M-mailbox load. For a buyer making a multi-year infrastructure commitment, the track record is the cost of the unknown.

Maildoso's 4.7 G2 rating (159 verified reviews) is unusually high for the category and reflects the operational reality more than the headline price.

Key takeaways

400,000+ mailboxes under management
10M+ daily sends processed at platform scale
4.7 G2 rating from 159 verified reviews
Operational track record newer providers cannot demonstrate

The SMTP-vs-Combo choice is the most-overlooked pricing lever

Maildoso's pricing publishes two tiers: pure SMTP ($1.90-$2.50) and Combo ($2-$3, SMTP plus Google Workspace). The naming undersells the impact. Pure SMTP runs through Maildoso's own sending fabric and lands in the inbox based on Maildoso IP reputation.

Combo mailboxes route through Google Workspace, which means the actual delivery path uses Google's MX servers and benefits from Gmail-to-Gmail inbox preference behavior. The deliverability differential is real but workflow-dependent. Sending to a B2B target list dominated by Google Workspace recipients, Combo typically lands 5-15 percent better in the inbox.

Sending to a mixed Microsoft 365 / corporate-IT-server list, the differential narrows or reverses. The 30-60 percent premium for Combo (typically $0.50-$0.80 more per mailbox) is worth it only when the recipient mix actually favors Google routing. The optimization most teams skip: run a 30-day deliverability test on a representative sample (say 5K sends each through SMTP and Combo) and pick the tier based on data, not assumption.

Most teams default to pure SMTP for cost and miss the placement gain; some default to Combo for reputation and overpay for routing they do not need.

Key takeaways

Pure SMTP: Maildoso fabric, lower cost
Combo: GWS routing, 5-15 percent better inboxing on GWS-heavy lists
30-60 percent cost premium for Combo over SMTP
Pick the tier based on a recipient-mix test, not assumption

The MCP and API support is a pricing-relevant feature at scale

Maildoso ships API access and MCP (Model Context Protocol) support, which most competitors do not. At 50-mailbox scale, API access is a nice-to-have. At 500-mailbox scale, manual provisioning becomes operationally infeasible: every new domain, every mailbox naming convention, every DNS verification adds up to hours of clicking through panels.

The API and MCP integration are what make Maildoso's scale claim (400K mailboxes managed) credible for individual large customers. The pricing-relevant implication: a 500-mailbox fleet on Maildoso can be provisioned in a few hours of scripting. The same fleet on a provider without API access is days of manual work plus ongoing fleet-management overhead.

The cost of operator time at $80-$150/hour quickly exceeds the per-mailbox savings if the alternative provider is API-less. For agencies and large in-house teams modeling total cost, this is the line item that does not appear on the pricing page but determines real-world economics at the high end of the scale range.

Key takeaways

API and MCP support for automated provisioning
Critical at 500+ mailbox scale where manual is infeasible
Operator time savings can exceed per-mailbox cost differential
A pricing factor that does not appear on the public sticker

When Maildoso is structurally the right pricing choice

Maildoso fits cleanly when three conditions hold. First, your sending platform already covers warmup, validation, placement testing, and blacklist monitoring; the savings on raw mailboxes is genuine because you are not buying duplicate deliverability tooling. Second, your volume is high enough that the per-mailbox rate difference materially matters; under 30-50 mailboxes the absolute dollars are too small to justify a separate infrastructure choice.

Third, you value operational continuity at scale over the pricing model of a newer provider with comparable rates. Maildoso does not fit cleanly when those conditions invert. Teams running barebones sequencers without deliverability tooling pay the gap to InboxKit and get the bundle.

Teams running small fleets pay the same amount across any provider. Teams comfortable with newer providers can match Maildoso's rate at Mailforge ($2-$3) or beat it on bundled value at InboxKit ($2.50). The selection question is which trade-off matches the operating model.

Key takeaways

Best fit: sending platform covers deliverability, high mailbox volume
Poor fit: small fleets, no separate deliverability tooling
Trade-off: cheapest rate vs bundled deliverability stack
Operational track record favors large-scale commitments

Keep reading

Sources

maildosoG2 Website

sendkitG2 Website

frequently asked questions

Got questions? We've got answers.

When your sending platform does not already cover warmup, verifier, placement testing, and blacklist monitoring. Sourcing those standalone runs $75-$200/mo regardless of mailbox count, which erodes the per-mailbox savings versus a bundled provider. At 100 mailboxes, raw Maildoso ($190) plus standalone tooling ($75-$150) lands at $265-$340, vs InboxKit at $250 all-in.

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