Google Workspace vs Outlook vs Managed Inboxes for Cold Email: Cost and Trade-offs

Once you decide to send cold email from separate domains, the next question is where the inboxes live. There are three common answers: Google Workspace, Microsoft (Microsoft 365 or Exchange Online), or managed sending inboxes that someone else buys and maintains for you. The right choice depends on how many inboxes you need, how much setup you want to own, and what you're willing to give up.

Below is the honest comparison, including the parts that don't favor us.

The cost of 100 inboxes

These are list prices per user on annual plans, which we checked on November 11, 2026. They exclude domains, taxes and promotions.

This is a price comparison, not a like-for-like product comparison. Google Workspace and Microsoft 365 include office apps, file storage, video calls and admin tools. Managed sending inboxes are built for one job: sending and receiving outreach email. If you'd use the extra apps, that changes the math.

Domains cost extra with Google and Microsoft, typically a modest yearly fee per domain at most registrars. With our managed inboxes, the domain is included.

Google Workspace

What you get: Gmail's interface, Google's infrastructure, and the full Workspace suite for every user.

Strengths:

• Familiar to almost everyone, and works with every major sending tool.
• Google publishes clear sending limits: 2,000 messages a day per user, lower for trial accounts, with additional caps on recipients per day.
• Strong admin tools, and DKIM is easy to switch on in the Admin console.

Trade-offs:

• Cost scales per inbox. At $7 per user, 100 inboxes is $700 a month before domains.
• Setup is yours. Each domain needs adding and verifying, plus SPF, DKIM and DMARC, and each inbox needs creating, configuring and connecting to your sending tool.
• Trial limits. New trial accounts have lower sending limits, and Google says limits for paid accounts only rise once the domain has paid at least $100 cumulatively, which can take up to 75 days to apply.
• Policy risk. Google's spam and abuse policy applies, and accounts that send spam can be restricted.

Microsoft 365 and Exchange Online

What you get: Outlook mailboxes on Microsoft's infrastructure. Microsoft 365 Business Basic adds Teams and web versions of Office apps. Exchange Online Plan 1 is email only, which makes it the cheapest of the big-provider options.

Strengths:

• Exchange Online Plan 1 is the lowest list price of the big providers, at $4 per user.
• Works with most sending tools.
• Some teams like spreading volume across both Google and Microsoft infrastructure rather than relying on one.

Trade-offs:

• Still per-inbox pricing. 100 inboxes is $400 to $700 a month depending on plan.
• Setup is yours, with Microsoft's admin center, DNS records and DKIM configuration for each domain.
• Limits are layered. Exchange Online applies a per-mailbox recipient rate limit over 24 hours, plus a tenant-wide limit on external recipients that depends on how many licenses you have. Read the current limits before you plan volume.
• Policy risk, as with Google. Microsoft's terms prohibit spam, and Outlook.com has required authentication from high-volume senders since May 2025.

Managed sending inboxes

What you get with ours: one sending domain with up to 100 inboxes for $69.99 a month, and each extra domain with 100 inboxes for another $69.99 a month. We buy and maintain the domain, keep SPF, DKIM and DMARC current, handle renewals, and connect the inboxes to your sending tool with warmup on.

Strengths:

• Much lower cost per inbox at volume.
• No setup work for you: no DNS, no admin consoles, no renewals.
• Authentication handled and kept current.

Trade-offs, honestly:

• You don't own the domains or inboxes. They stay with Plaintext if you cancel. With Google or Microsoft, you own everything. If owning your sending infrastructure matters to you, that's a real reason to choose them.
• No office suite. These inboxes are for outreach only.
• 100 inboxes on one domain still means one domain's reputation. Inbox providers judge volume per domain as well as per inbox. Spreading volume across 100 inboxes doesn't make a sudden jump in a domain's total volume any less sudden, so the domain still needs a gradual ramp and sensible caps. If a domain's reputation drops, all of its inboxes are affected. Teams sending at real volume should use more than one domain.
• No one can guarantee inbox placement, on any of these options. Ours included.

Which should you choose?

Whatever you choose, the fundamentals don't change: separate sending domains from your main domain, SPF, DKIM and DMARC on every domain, a gradual warmup, daily caps per inbox, clean lists and a working opt-out.

A setup checklist for any provider

1. Register sending domains close to your brand name, and redirect their websites to your main site.
2. Add MX records so the domains can receive replies.
3. Publish SPF (one record, under 10 lookups), switch on DKIM signing as your domain, and add DMARC starting at p=none with reports. Our SPF vs DKIM vs DMARC guide covers each one.
4. Create inboxes with real names, photos and signatures.
5. Connect them to your sending tool, with a custom tracking domain if you track clicks.
6. Ramp volume gradually and keep daily caps well below provider limits.
7. Verify the domains in Google Postmaster Tools and watch spam rate and bounces.
8. Confirm everything with a free email health check.

How we can help

If you want to own the setup, our Setup Sprint builds it for you on your own Google or Microsoft account: up to 3 sending domains and 9 inboxes, fully authenticated and connected, with a written ramp schedule. If you'd rather not manage inboxes at all, managed sending inboxes are $69.99 a month per domain with up to 100 inboxes each.