Maildoso Review: Features, Pros and Cons, Pricing Breakdown in 2026

An unbiased Maildoso review: cheap shared-pool inboxes with fast setup, but mixed deliverability, a 2025 blacklist incident, and unpredictable support.
Maildoso

Table of Contents

I have spent a lot of time testing and reading about cold email tools and what people talk about in different communities. Maildoso’s name comes up very often. Their pitch is easy – cheap inbox, instant setup, single dashboard for both Google and SMTP.

However, the reviews were mixed. Some people on the forums called them reliable. While others shared their bad experiences. In this unbiased Maildoso review, I will try to separate the marketing promises from real-life experiences of multiple users.

Full disclosure: Aerosend is my company and competes with Maildoso. This review is not biased or altered. The information mentioned in this Maildoso review is thoroughly fact-checked and supported by evidence from reliable sources.

Key Takeaways

3.0out of 5
★★★★★★★★★★
Our Verdict =Average
Value for Money3
Features3
Support2.5
Deliverability2

If you want to run an email campaign on a budget, you can buy inboxes from Maildoso. It is a cold email infrastructure that provides Google Workspace inboxes and registers domains (for additional cost). Their setup is quick and easy, suitable for cost-conscious agencies and operators who want fast, cheap mailboxes.

  • Consumer: Cost-Conscious Agencies and Solo Operators
  • USP: Setup speed and price. Auto-configured mailbox at $2.5
  • Deliverability Success: Mixed Reviews
  • Risk: Volatile deliverability of the shared pool
  • Starting Plan: $75 per month for 30 mailboxes
  • Support: Mixed Reviews

Due to their history of blacklist and burned-domain incidents, their shared sending pool infrastructure is a risk.

About Maildoso

Maildoso is a cold email inbox provider where you can buy Google Workspace and SMTP inboxes (minimum 30). It auto-configures SPF, DKIM, and DMARC. But you need a sequencer like Smartlead or Instantly to actually run the campaigns.

The company ran into trouble in November 2025 when their server was blacklisted which impacted hundreds of Maildoso customers.

How Maildoso Works

Maildoso Google Workspace Inbox
Maildoso provides Google Workspace + SMTP inboxes.
Maildoso Homepage
Maildoso Homepage
Maildoso Inbox Pricing
Here's the latest inbox pricing of Maildoso inboxes.
Maildoso SMTP Inboxes
Maildoso offers SMTP inboxes in monthly and quarterly plans.
How to set up Maildoso account?
How to set up Maildoso account?

Maildoso Features

Inboxes on a Rotating Shared Pool 3.5 / 5

Maildoso hosts your inboxes on a rotating pool of IPs that it owns end-to-end. Meaning: your inboxes are linked to multiple IPs which are also used by other customers. If the IP is flagged for spammy practices, all the inboxes tied will be affected.

Now your deliverability success is relying more on how other inboxes are sending cold emails than your own cold emailing strategy.

Resell Google Workspace Inbox 3.5 / 5

It resells authentic Google Workspace inboxes. The provisioning generally takes up to two hours, and sequencer connection takes up to 24 hours.

Regular Inbox Placement Tests and Health Scores 2.5 / 5

Maildoso runs regular automated inbox placement tests and shows a health score per inbox in the dashboard. A user can check burn and blacklist status of its inboxes. But, the accuracy of the score is still unknown.

Burned Inbox Remedy 3.5 / 5

When the system detects a burned inbox, it pauses the inbox from active campaigns, and sets it aside for 14 days for rotation. It automatically triggers the auto-cooldown when the bounce spikes.

Shared Tracking For Link and Image 2.5 / 5

Using Global Customer Domain Tracking, Maildoso auto-substitutes the links and images in your emails as safe and trusted. You can mention a booking link or CTA into your first email as it won’t affect your deliverability.

Pros

Fast Setup

Setting up DNS across multiple inboxes takes up the whole day. With Maildoso, you can connect multiple inboxes to your sequencer and go live in a couple of hours.

Cost Effective

The actual cost of a Maildoso inbox is $2.50 per mailbox. When you buy in bulk, you’ll get it even for less. It’s cheaper than most cold email service providers’ list prices too.

Built-in Proactive Deliverability Tools

Maildoso includes monitoring features which many cold-email providers don’t offer. You get regular inbox placement tests, and a health score for each inbox. Also it notifies you when the inboxes are burned or blacklisted, with an auto-fix option that pauses affected inboxes.

Proactive Support

The Maildoso support team often offers solutions such as audits and domain swaps to users. The founder has even reached out personally during blacklisted event for clarifying the situation.

Cons

Shared IP Pool Risk

Maildoso hosts inboxes on its shared IP infrastructure. In this case, your deliverability rate depends on the performance of other inboxes on the same IP. For example, if someone in the pool is sending “You’ve won $10,000, send us your bank details to collect the money” and attaches a poorly Canva-ed “Lottery Winner” jpg, the impact of the Lottery campaign will be shared across all the inboxes connected to the IP. Many Maildoso users flagged its shared IP infrastructure and faced deliverability issues.

“the IPs are shared with cold emailers only, which increases the chances of getting blacklisted… make sure you are using an email warm up service and always keep it on.”

u/msham01, r/LeadGeneration

“around week 7-8… about 12 of the SMTP mailboxes started landing in spam more frequently… just a batch that seemed to share similar IPs.”

u/NoWorldliness9061, r/coldemail

Findings from the test: Your campaign is only as good as your IP neighbors.

Blacklist and Burned-Domain Incidents in 2025

In late-2025, Maildoso had a network-wide blacklist event, which saw its domains burned faster than Barry Allen’s top speed. Every Maildoso users saw their domains blacklisted and lost hundreds of thousands of business overnight. 

“Looks like they are in big trouble, their IP pool and domains are listed SURBL multi blacklist.”

u/Antosha-Potato, r/coldemail

“Every single domain was burned in a single day because of a ‘large scale issue’ they were facing. They replaced all the domains with .click .top .xyz emails, which affect deliverability.”

Verified User in Consulting, G2

Quarterly Plans for the Best Value

The cheapest Maildoso per-index rate of $1.80 is applicable only on the Maildoso quarterly plan which is billed at $2,199/qtr and includes 400 inboxes. In this plan you will also get 100 domains free which will be on shared IP.

Note: There’s no free trial.

“They are just eating the cost of domains. They make up for this by locking you into a 3 month payment plan.”

u/Little_Bowler7849, r/LeadGeneration

Thin Reporting From Basic Dashboard

Maildoso dashboard is pretty generic and the in-app analytics is very thin. For actionable data, users usually prefer to pull data from the sequencer instead.

“dashboard analytics are a bit thin… I have to pull data from my sequencer to really see the health of specific domains, internal view is quite basic.”

Small-Business reviewer, G2

Maildoso Pricing

Maildoso offers monthly and quarterly plans across different inbox combinations. Here is the full Maildoso pricing breakdown.

All plans include

  • Mailboxes on the rotating pool · Auto SPF/DKIM/DMARC · IP rotation
  • Self-healing recovery · 3-day placement tests · Health scores · Link safety
  • 30-day money-back guarantee (monthly plans)
Category Billed Inboxes Price Price / Mailbox Domains
SMTP Monthly 30 $75 $2.5 Not included
SMTP Monthly 70 $158 $2.25 Not included
SMTP Monthly 300 $570 $1.9 Not included
Combo: SMTP + Google Workspace Monthly 15 GW + 15 standard $90 $3 each Requires 6 (not included)
Combo: SMTP + Google Workspace Monthly 35 GW + 35 standard $175 $2.5 each Requires 14 (not included)
Combo: SMTP + Google Workspace Monthly 150 GW + 150 standard $675 $2 std, $2.5 GW Requires 60 (not included)
Quarterly SMTP Quarterly 32 $299 $3.1 8 free
Quarterly SMTP Quarterly 68 $499 $2.4 17 free
Quarterly SMTP Quarterly 400 $2,199 $1.8 100 free

Combo plans add isolated Google Workspace inboxes alongside the standard side.

Value for MoneyAverage3/5
  • Per-mailbox pricing is cheap (Minimum 70 inboxes)
  • Free domains on quarterly plans (Applicable only on Quarterly Plans)
  • Deliverability risk on the shared IP pool
  • No free plan or trial · paid subscription model
Note:

  • The “$1.8/mo” inbox is applicable on the 400-mailbox quarterly plan, billed at $2,199 paid up front.
  • Lowest inbox price is $2.5 per inbox, or $75 per month for 30 mailboxes.
  • A domain costs $12/year and is included free only on quarterly plans.
  • The sending limit is 15 cold emails per day per mailbox. To run at volume you need more inboxes (and more domains for Google Workspace mailboxes).

Maildoso vs Aerosend

Maildoso and Aerosend solve the same problem: inbox provider for cold outreach. But the difference in infrastructure justifies the pricing.

Maildoso is a budget cold-email service provider. You can buy inboxes at lower cost, setup is quick, connects a sequencer, and manually runs warmup before cold emailing. The disadvantage of Maildoso inbox is shared IP pool infrastructure. It uses rotating IP pool for inboxes which shares the IP with multiple cold-email senders. Which is why their cost per mailbox is low. Also the risk is huge as one bad IP neighbour can burn the IP and connected inboxes.

About Aerosend

Dedicated Private Infrastructure

  • Managed deliverability service built on dedicated, private infrastructure.
  • Every 10 domains sit on their own server with their own aged IPs.
  • IPs are geography-matched: North American IPs for North American prospects, European IPs for European ones.

Managed Deliverability Layer (run for you)

  • Complimentary premium warmup which monitors 6-7 warmup providers, warms inboxes through WarmupInbox.com.
  • If a provider degrades, we move you off it so placement holds.
  • Warmup volume matched to who you actually email.
  • Biweekly seed-list placement tests for every client.
  • 5-metric burn detection system that flags domains before its placement drops.
  • Proactive IP rotation.
  • Free domain reprovisioning if a domain does burn.

Track Record

  • 95-99% inbox placement range.
  • Longest live domain: 14 months.
  • Zero blacklist presence across operating history, monitored daily against Spamhaus, Barracuda, and SURBL.
Dimension Maildoso Aerosend
Infrastructure model Shared SMTP IP pool (cold-emailer-only) + Google Workspace reseller Dedicated private server per 10 domains, aged IPs never shared
IP isolation Rotating pool shared across customers Private IPs, one customer only; NA-for-NA, EU-for-EU geo-matching
Per-mailbox price (entry) ~$2.5/inbox ($75/mo, 30 SMTP) $4/inbox (first 150 inbox)
Per-mailbox price (scale) $1.9/mo (300 monthly) down to $1.8/mo (400 quarterly) $2/inbox beyond 150 inbox
Warmup No dedicated warmup. User manually runs via sequencer Complimentary premium warmup from warmupinbox.com ($40/inbox) and matched recipient ESP mix
Cold Emails / Day 15 25
Inbox placement testing Automated every 3 days; methodology not disclosed Biweekly seed-list tests (Gmail/Outlook/Yahoo) for every client
Burn handling Reactive: 14-day auto-pause after a inbox is flagged burned Proactive: 5-metric burn detection before placement drops + free domain reprovisioning
Documented incidents Network-wide SURBL blacklist + burned domains, 2025 (recoverable) Zero blacklist presence / zero mass bans in operating history
Deliverability accountability Self-serve; you own monitoring and recovery Managed; we monitor 24/7 and intervene; reply-rate guarantee
Billing / lock-in Monthly or quarterly; best price + free domains require a quarterly prepay Monthly, no long-term contract
Free trial No free trial; 30-day money-back on monthly SMTP only No free tier (free deliverability tools available)
Support model Chat + email + Slack community; no tiered support; bimodal in practice 24/7 monitoring + monthly reports; expert brainstorm with the founder; dedicated Slack + priority support past 150 mailboxes

Price/Mailbox Breakdown (~5,000 emails/day)

Requirements Maildoso Aerosend
Inboxes needed ~334 (sizes to 400 plan) 200
Send rate per mailbox 15 20-25/day
Plan 400-mailbox quarterly 150 @ $4 + 50 @ $2
Per-inbox rate $1.80 $3.50 (blended)
Monthly total ~$733 ~$700
Service model Self-managed Managed
Note: Comparing Maildoso and Aerosend on per-inbox price alone. At a baseline of about 750 emails a day, Maildoso needs roughly 50 inboxes at its 15-per-day ceiling, which lands near $120 to $158 a month and leaves the deliverability work to you. You need 30 inboxes at 20-25 per day cold email frequency, which is $120 a month with the managed layer included on Aerosend. The lower per-inbox sticker is offset by needing more inboxes.

Maildoso Support

Support RatingAverage2.5/5

Maildoso’s primary support channel is a website chat widget. Users can also email help [at] realmaildoso [dot] com. Support hours run US Eastern, 2 AM to 5 PM.

Maildoso Support Review

The Maildoso account is active on Reddit resolving complaints and offering audits and domain replacements. The founder has personally reached out to users during incidents, like the 2025 blacklist event. But their support received mixed reviews.

“they keep your account on hold… they have not solved it for 45 days. On continuous follow-up then simply stop responding.”

G2 reviewer

Even a happy 5-star user had to go through a four-hour chat wait to get the problem resolved.

The Verdict

OverallAverage3/5

If you’re new to cold emailing and want to run a campaign at low volume, Maildoso is a strong option. Cheap inboxes, automatic DNS setup, reasonable tracking, and the flexibility of Google Workspace and SMTP inboxes. You can also monitor the performance of your campaign. The drawbacks: the shared IP pool which affects deliverability and reply rate, lack of support, and a history of blacklisting due to spammy activities.

While Aerosend costs more per mailbox, you’re investing in best-in-class deliverability and reply rates, dedicated IPs, and Namit on support 24/7.

Frequently Asked Questions About Maildoso

 

How much does Maildoso cost?

Maildoso's monthly starter plan starts at $75 per month for 30 mailboxes, about $2.5 each per mailbox.

Did Maildoso get blacklisted?

Yes. In mid-2025, multiple users independently reported that Maildoso's shared IP pool and domains were listed on the SURBL blacklist, disrupting campaigns network-wide.

Why do Maildoso domains get burned so fast?

The most common cause cited by users across Reddit and G2 is the shared IP pool. The same IPs are used by multiple cold emailers and if any domains get flagged, it can bring down the IP and deliverability rates.

Does Maildoso include warm-up, and is it free?

Maildoso does not run warm-up. Your connected sequencer like Smartlead and Instantly runs warm-up.

Does Maildoso support Microsoft 365 or Outlook?

No. Maildoso offers its own mailboxes and resold Google Workspace mailboxes only. There is no Microsoft 365 or Outlook option at any price.

Is Maildoso a full cold email infrastructure?

Maildoso is a full cold email infrastructure. But you need to connect to a sequencer like Smartlead and Instantly to actually send cold email.

Does Maildoso offer a free trial or money-back guarantee?

Maildoso has no free trial. It offers a results-based 30-day money-back guarantee on monthly plans.

Does Maildoso have an API?

Yes. Maildoso provides a public API that supports connecting external domains.

Maildoso vs Aerosend: which is a better email infrastructure tool?

It depends on who should own your deliverability. Maildoso is cheaper per mailbox and self-serve on a shared IP pool. Aerosend costs more but runs on dedicated private IPs and manages warm-up for your mailboxes, conducts placement testing, and burn detection for you.

Coming Soon
SPF/DKIM/DMARC Checker Soon

Validate your email authentication

Blacklist Checker Soon

Check if your domain or IP is blacklisted

Email Spam Checker Soon

Test if your email lands in spam

How to Get Your Instantly API Key
Step 1 : Log in to Your Instantly Account
Go to https://app.instantly.ai/auth/login and log in to your account
Step 2 : Navigate to Settings

Click on your profile icon in the bottom-left corner, then select “Settings” from the dropdown menu.

Step 3 : Select Integration

In the Integrations page, click on the “API Keys” tab in the left sidebar.

Step 4 : Get Your API Key with all:read Scope

If you already have an API key with the all:read scope, you can use that key.


If not, click the “Create API Key” button, select the all:read scope, and make sure to save your new API key somewhere safe.

How to Get Your Smart Lead API Key
Step 1 : Log in to Your Smart Lead Account
Go to https://app.smartlead.ai/login account and log in to your account
Step 2 : Navigate to Settings

Click on the “Settings” option in the top right corner profile icon.

Step 3 : Select API Integration

In the Settings page, under your profile picture, you can see the SmartLead API Key.

Step 4 : Generate Your API Key

If you already have an API key displayed, you can use that key. If not, click the “Generate API Key” button to create a new one.