Single sign-on (SSO): An authentication arrangement in which one identity provider verifies a user once and then grants access to multiple separate applications without a new login for each.
Also known as: SSO, Federated login
Key takeaways
- SSO lets one company identity unlock many applications.
- It relies on standards such as SAML or OpenID Connect between an identity provider and each app.
- The main benefit is central control; the main risk is that one compromised login opens many doors.
- C Chat does not offer SSO; people sign in with a one-time code sent to their phone or email.
- Owners and admins control access by adding and removing people from the team.
As companies adopt more cloud apps, every new tool brings another username and password. Single sign-on is the standard answer from IT departments. It is worth understanding what SSO actually does, what it does not do, and how it compares with the passwordless login used by tools like C Chat.
Single sign-on (SSO): a plain definition
SSO means one login, many apps. An employee authenticates once with an identity provider (the company’s directory service), and connected applications trust that provider’s confirmation instead of asking for their own password.
The practical result: staff remember one credential, and IT has one switch to turn access on or off.
How it works
Under the hood, SSO is a trust relationship between two parties:
- The user opens an app and chooses to sign in with the company account.
- The app redirects to the identity provider, which checks the user’s credentials and any second factor.
- The provider sends back a signed assertion (in SAML) or a token (in OpenID Connect) saying who the user is.
- The app verifies the signature and opens a session without ever seeing the user’s password.
The security of the whole chain depends on the identity provider. That is why SSO deployments almost always require two-factor authentication at the provider.
Why it matters for business messaging
Messaging apps hold operational details, client information and photos from the field. Two questions matter most for any chat tool: who can get in, and how fast can you lock someone out. SSO answers both centrally for organizations that already run a directory.
It has limits, though. Many frontline workers, contractors and guests never get a corporate account, so SSO alone doesn’t cover everyone who needs to be in the conversation. And a phished SSO login is more damaging than a phished single-app password.
How it relates to C Chat
C Chat does not offer SSO. Instead it uses passwordless authentication: you sign up with your phone number and receive a code by SMS, or with your email and receive a code by email, much like WhatsApp. There is no password to reuse or leak. The details are on the passwordless sign-up page.
Access control happens at the team level. Owners and admins invite people by link, QR code, WhatsApp, SMS or email, and remove them when they leave. Guests such as contractors or clients join a specific group by invitation, which suits people who would never have a company directory account.
Related terms and common misconceptions
- “SSO and passwordless are opposites.” Not really. Both remove the need for one password per app; SSO centralizes the login, while passwordless replaces the password with a code or device proof. See whether passwordless login is secure.
- “SSO removes the need for one-time codes.” Identity providers usually add a one-time passcode or an app prompt as the second factor.
- “With SSO, SIM swaps don’t matter.” If the provider sends codes by SMS, a SIM swap attack can still be a weak point.
For a broader picture of how sign-in, access and oversight fit together, see the security overview.
Getting started
If you want a team messenger that frontline staff, contractors and office workers can all join with just a phone number or email, create your team at getcchat.com/c. It is free for now within the limits listed on the pricing page.
Frequently asked questions
What is the difference between SSO and 2FA?
SSO is about how many logins you need: one identity for many apps. Two-factor authentication is about how strong a single login is: it requires a second proof besides a password. Many companies combine them, requiring 2FA at the identity provider.
Is SSO more secure than separate passwords?
Usually, because people reuse fewer passwords and IT can revoke access centrally. But it creates a single point of failure: if the SSO account is phished, every connected app is exposed, so it should always be paired with strong verification.
Does C Chat support single sign-on?
No. C Chat does not offer SSO. Each person signs up and logs in with a one-time code sent by SMS to their phone number or by email, without a password. Team owners and admins manage who belongs to the team.
Do small businesses need SSO?
Not always. SSO pays off when you manage many apps and many employees through a central directory. A small team with a handful of tools can often get similar control by using apps where an owner can add and remove people quickly.