Google Groups for Business: Limits, Shared Inboxes and Admin Traps

Here's the catch most admins miss. The hourly sending numbers are added up across every group in your account, so one message sent to five groups counts five times. And if you're still on a trial, group mail only reaches people inside your organisation, so testing a mailing list on a trial tells you nothing about how it'll behave with customers.

Google Group or Contacts group: pick the right one

People mix these up all the time, and they're not the same thing. A Contacts group is a list for one person's own use. A Google Group has its own email address that anyone with permission can write to, it can be shared on Docs and Sites, and it supports moderation and conversation history.

	Contacts group	Google Group
Who it's for	One person	A team or a whole organisation
Its own email address	No	Yes
Shared on Docs and Sites	No	Yes
Moderation and history	No	Yes

Groups made in the Admin console come in four types: mailing lists, collaborative inboxes, configuration groups and dynamic groups. The last two can only be created in the Admin console or through the API. If all you need is a list of people you email together from your own account, my guide to making a group email in Gmail is the quicker route.

Google Groups limits at a glance

Google lists these limits for Groups for Business as of October 2026, and says they can change without notice:

Limit	Amount
Individual message size	25 MB
Emails per sender to any one group	1,800 per hour
Inbound emails per group	300 per 5 minutes
Total message size a group can send	2.4 GB per hour
External recipients per group	50,000 per day, and 5,000 per 10 minutes
External recipients per Workspace account	100,000 per day up to 10,000 users, 1,000,000 per day above that
Emails per internal sender, across all groups	18,000 per hour
Emails per external sender, across all groups	1,800 per hour

External senders who aren't Workspace customers get a lower limit than that 1,800. When any limit is hit, the activity is restricted for a while, typically an hour but sometimes as long as 24 hours.

Why the per-hour numbers bite sooner than you'd expect

The phrase that matters is across all groups. If a manager sends one update to the sales, support and leadership groups, that's three emails against the hourly count, not one. Add a few automated notifications landing in the same groups and a busy morning can trip a restriction you didn't think you were near.

The same logic applies to the 2.4 GB per hour a group can send. A handful of large attachments going out to a big group burns through it faster than the message count suggests, because every copy counts.

Members, invitations and group ownership

There's no cap on how many members a group can hold, but there are caps on each person and on how fast you can add people.

• Direct memberships per user are roughly 3,600, and direct plus indirect roughly 9,000. Owners and managers count as two memberships each, so heavy group owners hit the ceiling first.
• In the web interface you can add 200 members per session, but only 10 external people before a CAPTCHA appears.
• Each group and each user can send 500 external invitations per day and approve 100 external join requests per day. A user can join 30 external groups per day.
• Each user can create unlimited groups but own 1,500 at once, and create 5 external groups per week, with 50 per week from one IP address.
• Each customer gets 500 dynamic groups, and Support can raise that case by case.
• Members of an external group can post 100 times a day before a CAPTCHA, and 500 a day after it, including the first 100.

A collaborative inbox for support@ or sales@

This is the type I'd point most small businesses to. A collaborative inbox turns a group address into a shared workload: members can take a conversation, assign it to someone, unassign it, and resolve it as complete, no action needed or duplicate. The person assigned gets an automated email, with an optional note from whoever assigned it.

One limit to know: forwarding or copying from a collaborative inbox is capped at 25 addresses per message. That's plenty for passing a customer query to a colleague, but it rules out using the inbox to blast replies to a list.

Rolling out a group without hitting a wall

1. Get off the trial before you test anything with outside recipients, because trial groups only deliver inside your organisation.
2. Pick the type first. Create configuration and dynamic groups in the Admin console, since you can't make them anywhere else.
3. Add external members in small batches. After 10 in one session you'll hit a CAPTCHA, and 200 is the per-session ceiling.
4. Send one message to one group where you can. Every extra group multiplies the hourly count.
5. Keep big owners under 1,500 groups and watch memberships, remembering owners count double.
6. For support@ or sales@, use a collaborative inbox and keep forwards to 25 addresses or fewer.

Which Workspace editions include Groups for Business

Groups for Business is available in every Workspace edition, including the legacy free G Suite. The legacy free edition can't post messages, moderate or save conversation history, though, which takes out most of the reasons to use it.

Trial accounts carry their own restrictions. Sending limits are lower, group email only goes to recipients inside the organisation, there are no autoreplies to outsiders, and you can't let messages flagged as spam post directly. If you're still choosing a plan, my breakdown of Google Workspace plans sets the editions side by side.

My verdict on Google Groups for a small business

I'd set up a collaborative inbox the day two people start answering the same customer emails, because assigning and resolving beats forwarding threads around and hoping someone replies. I'd keep each message to one group, since that per-hour count is shared. And I'd skip a Google Group entirely if it's only you emailing the same few people, because a Contacts group does that job without any admin.

Getting your shared inboxes working is one part of running a small team well. Getting that team working well with AI is where I come in. I run AI training and workshops for teams, and help businesses with AI enablement, AI automation and GEO, which is about getting your business seen and cited in AI answers. Most of that work is with SaaS marketing teams, telecom companies and small businesses. Here's how we can work together.

Frequently asked questions

How many members can a Google Group have?

There's no limit on total members per group. The limits sit on each person: roughly 3,600 direct memberships per user, or roughly 9,000 direct plus indirect, and owners and managers count twice.

What is the sending limit for Google Groups?

As of October 2026, each sender can send 1,800 emails per hour to any one group, and internal senders can send 18,000 per hour across all groups combined. A group accepts 300 inbound emails per 5 minutes.

Can Google Groups email people outside my company?

Yes, up to 50,000 external recipients per group per day. On a Workspace trial, though, group email only reaches people inside your organisation.

What is a collaborative inbox in Google Groups?

It's a group where members can take, assign, unassign and resolve conversations, which makes it a shared inbox for an address like support@.

What happens when a Google Group hits a limit?

Activity is temporarily restricted, typically for an hour but sometimes for as long as 24 hours.