Does QuickBooks Online support Single Sign-On (SSO) with Office 365 or Azure Active Directory?

I'm in agreement with all others on this thread - QBO should definitely add the ability to integrate with other identity providers (Google, AzureAD, or any SAML provider). Sure it is great that Inuit has an Oauth 2 system for integrations, that makes sense for sure, but the support people in this thread and elsewhere in the developer pages aren't getting that we IT administrators are also looking for a way for our QBO end users (our accountants, etc) to sign into to QBO using the identity provider that our company uses for literally everything else.

Since QuickBooks Online can authenticate users via OpenID Connect, it can absolutely be set up to work with most modern IdPs, including Azure.

Apparently, the support rep that replied (as well as the ones who suggested you request the feature, lol) didn't understand your question. Quite often, you'll note that rather than ask clarifying questions or check with a colleague, the reps simply answer "no" to questions they don't understand. This is unfortunate as it undermines their credibility.

The average person has approximately 90 different internet accounts, that's a lot! That means most people have many different usernames and passwords they have to remember. From a security perspective this is a concern.

Federated Identity Login would allow you to login using a service such Microsoft Office 365

Most Online Services for Enterprises these days are subject to ISO Certification reviews by their clients. SSO is important to ensure adequate internal controls. This allows passwords to be centrally managed, and users to be immediately locked out upon leaving the company without going to various numerous platforms.