InboxKit:
The Ultimate Review (2026)

InboxKit is a cold email infrastructure platform that provides official US-IP Google Workspace, Microsoft 365, and Azure mailboxes with automated DNS setup (SPF, DKIM, DMARC), isolated warmup, and 24+ sequencer integrations (Smartlead, Instantly, Lemlist, Apollo, and more).

Launched in the mid-2020s by founder Rahul Lakhaney and operated under Enrich Labs out of Dubai, UAE, it targets agencies and sales teams running outbound campaigns.

What sets it apart: it is the only official Google Cloud partner in this niche, guarantees a 95% inbox placement rate, ships full API access, and bundles InfraGuard – 24/7 blacklist, DNS, and bounce monitoring – with isolated admin panels per domain to prevent cross-contamination.

G2: 4.9/5 (37 reviews)

"InboxKit not only offers official google, Outlook and Azure mailboxes at the best price but also offers Infraguard which monitors health of domains and mailboxes proactively and flags issues before it becomes an issue." – InboxKit vs premium inboxes for Google?

🟢 Integrated Warmup Tool: InboxKit includes a native warmup feature that helps new accounts gradually build volume within the same dashboard, making it convenient for beginners.
🟢 Clean, Intuitive Dashboard: The UI is very friendly and well-designed, which is great for small business owners who are managing their own outreach.
🟢 Centralized Infrastructure Hub: Manage Google, Microsoft, and SMTP accounts from one unified dashboard.

🔴 Static IP Infrastructure: Their servers rely on static IP pools. In 2026, this is a major risk; if an IP gets flagged, your entire campaign suffers until you manually rotate or request a new one.
🔴 Surface-Level Deliverability Support: Their support team is great at software questions but often lacks the deep technical forensic knowledge needed to solve complex email deliverability infrastructure drops.

Maildoso is a cold outreach infrastructure provider – we offer domains, SMTP mailboxes, and Google Workspace accounts. The company was founded in August 2023 in Granite Bay, California, by Nikita Bykadarov (Nikita Maildoso).

While other providers offer shared or dedicated IPs, we have developed IP rotation. This means your emails are sent from hundreds of different IPs (making it harder for spam filters to detect a sending pattern), and whenever any IP gets blacklisted, we automatically swap it out for a clean one.

We have also implemented self-healing mailbox technology, which both restores burned-out mailboxes and protects your active email accounts.

The result?
As of May 2026, the spam rate across our entire network of mailboxes is around 5%.

G2: 4.7/5 (181 reviews)

"Tried it mainly because of the good price, but ended up sticking with it since deliverability’s been pretty stable so far" – Thinking about trying "Maildoso". Has anyone here used it? Is it actually better than other tools?

"I tested a small batch first and results were comparable to our Google setup. Ended up moving more campaigns there because of the lower cost. That's a good strategy, buy small package and compare with your current setup" – I want to try Maildoso. What do you guys think about it?

🟢 Dynamic IP Rotation: We rotate your IP addresses in real-time – if an IP gets flagged or blacklisted, we instantly swap it for a clean one before your campaign takes a hit, ensuring your emails consistently land in the primary inbox rather than getting stuck in spam.
🟢 Self-Healing Rotation: An automated resting period for mailboxes every two weeks that clears provider flags and recovers reputation on autopilot.
🟢 Global Customer Domain Tracking: Proprietary technology that allows you to safely include links without compromising your sender reputation.
🟢 Automated Inbox Placement Tests: Free email deliverability infrastructure testing every three days for all mailboxes, giving you real-time visibility into your health.

🔴 Conservative Limits: We suggest sticking to 15 emails a day per box to keep your domains healthy for the long run.
🔴 Google/SMTP Focus: We do not support Microsoft 365/Outlook/Azure environments at this time.
🔴 Lack of built-in warmup. We do not have an integrated warm-up yet, but we are currently working on it.

It’s tempting to choose a provider based solely on the lowest price, but budget infrastructure often leads to hidden costs. When deliverability drops, the consequences usually show up in three areas:

• Burned Leads: High-quality B2B data is expensive. If emails land in spam, those contacts never see the pitch, and the budget spent on data is lost.
• Damaged Domains: Fixing a domain flagged by spam filters can be a massive headache. Often, it’s easier to just buy a new one and start the warm-up process all over again.
• Missed Revenue: Every missed inbox is a missed meeting. In B2B sales, losing even one connection can mean missing out on thousands in closed revenue.

Cold email infrastructure is better viewed as an investment. Maildoso provides the technical tools to protect domain reputation and help keep emails in the primary inbox.

To sum up, we can say that InboxKit is a fairly reliable provider and a worthy competitor.

We recommend giving InboxKit a try for your campaigns, especially their Google Workspace accounts.

In fact, we were surprised that despite having some market presence, there are almost no mentions of them on Reddit.

The only thing that raises concerns is their Azure tenants. We haven't heard of any successful use cases for these mailboxes—on the contrary, they seem to burn out extremely fast. Be careful with them.