Outlook or Gmail: which works better with a CRM for a 20 person firm?

When a firm chooses or replaces its CRM, someone usually asks whether the email platform should change too. Would Gmail make HubSpot easier? Would Outlook work better with the practice management system? Switching email is disruptive, so it is worth knowing whether it would actually help.

The direct answer: for a 20 person firm, neither Outlook nor Gmail is clearly better with a CRM. The mainstream CRMs and practice management tools used by law, accounting, clinic and consulting firms support both. What decides it is everything around the email: which office apps and file storage your team uses, how you handle shared inboxes, which devices and browsers people work on, and how your CRM's add-in behaves on each platform. In most cases, keep the email platform you have and configure the CRM connection properly.

Both are supported by the tools firms actually use

A few examples, as documented by each vendor in October 2026:

• HubSpot offers an Office 365 add-in for Outlook and a Chrome extension for Gmail, both with log and track features.
• Clio Manage offers an Outlook add-in and Clio for Gmail, both able to file emails, threads and attachments to matters.
• Karbon connects both Gmail and Office 365 accounts to its triage inbox.

So the question is not "which one does my CRM support", but "where are the small differences, and do they matter for us".

Where the differences show up

Add-in requirements and devices

Each integration has its own fine print, and it is worth reading before you commit:

• Clio's help article says its Outlook add-in needs Outlook 2016 or later with a Microsoft 365 Business subscription on a Microsoft-backed account, and may not work in Firefox or Safari by default because of third-party cookie restrictions.
• Clio for Gmail does not work in Google's Gmail app for iPhone and iPad, according to the same help center.
• HubSpot's Chrome extension does not support tracking and logging for customized Gmail layouts, and does not log non-inline attachments to the CRM.
• HubSpot's Outlook add-in only logs or tracks an email if its task pane is open when the email is sent.

None of these is a reason to switch platforms. They are reasons to test with the devices and browsers your team really uses, especially if partners work mostly from phones.

Shared inboxes

This is where firms hit real problems, on both platforms. Microsoft 365 shared mailboxes have no login of their own, and several CRMs cannot connect them as normal inboxes:

• HubSpot lists Microsoft 365 shared mailboxes as unsupported for individual inbox connections in its inbox connection article.
• Clio's help center says its Outlook add-in cannot be used for shared inboxes.
• Karbon's shared triage documentation says it does not currently support Outlook shared mailboxes or Google Groups.

Note the last point: Google's equivalent, a group used as a shared inbox, has the same kind of limitation in Karbon. If your firm runs client contact through info@ or accounts@, the shared-address design matters more than the email brand. Our guide to connecting Microsoft 365 to HubSpot covers the usual options: a team email channel, a licensed mailbox, or a tested workaround.

The rest of the suite

Email is rarely chosen alone. Outlook comes with Word, Excel, Teams, SharePoint and OneDrive; Gmail comes with Docs, Sheets, Meet and Drive. The CRM connection is usually a smaller decision than:

• Document work. Firms that exchange heavily formatted Word documents with clients, courts or other advisers often find Microsoft 365 smoother.
• File storage. Where client files live (SharePoint or Drive) affects every automation that files attachments or generates documents.
• Automation tools. Microsoft 365 business licenses include a limited version of Power Automate; firms on Google Workspace usually use Zapier, Make or similar. Our comparison of Power Automate vs Zapier explains the licensing.
• Your IT provider. Many small-firm IT providers specialize in one of the two. Switching platforms can mean switching support too.

A quick comparison

When switching email does make sense

Change platforms only for reasons bigger than the CRM, for example:

• the firm is already split across both, and merging onto one removes a duplicate set of licenses and admin work,
• your core practice or clinic system integrates far better with one platform, and you have tested it with real accounts, or
• you are moving file storage anyway, and email naturally follows.

Even then, plan the migration of mail, calendars, shared mailboxes, distribution lists and every automation that sends or reads email. A rushed switch breaks more CRM logging than it fixes.

What actually makes CRM email work

Whichever platform you use, the same five things decide whether client email ends up on the right record:

1. Every user connects their own inbox and has the add-in or extension installed, ideally deployed centrally by an admin.
2. Account-wide logging rules are set: which domains are never logged, whether replies log automatically, and who can see logged email.
3. A written route for each shared address, so enquiries are captured once.
4. One system owns client contacts, so address books do not sync duplicates into the CRM.
5. A short training session on the small rules, such as keeping the Outlook task pane open, with a one-page written guide people can return to.

For confidential work, decide what must stay out of the CRM before rollout, and check with your compliance lead what your professional rules require.

How Flow Mesh helps

A stack audit looks at your email platform, CRM and shared inboxes together and gives every tool a verdict (keep, configure, consolidate or replace), so you only switch platforms if it genuinely pays off. The audit is scoped in writing first, and any build is quoted in writing afterwards and carried out inside your own accounts.

Key takeaways

• HubSpot, Clio and Karbon all support both Outlook and Gmail; the CRM alone is rarely a reason to switch email.
• Shared inboxes are the common weak spot on both platforms, so design a route for each shared address.
• Test add-ins on the devices and browsers your team really uses, including phones.
• Choose the platform on the wider suite: documents, file storage, automation and IT support.
• Logging rules, one owner for contacts and short training matter more than the email brand.