What Is Single Sign-On (SSO)? How It Works for Business

What Is Single Sign-On?

Single sign-on (SSO) is an authentication method that allows users to log into multiple applications and services using just one set of credentials. Instead of remembering separate usernames and passwords for email, CRM, accounting software, and every other business tool, staff sign in once and gain access to everything they need.

For UK businesses managing dozens of cloud applications, SSO simplifies access, strengthens security, and saves IT teams significant time on password resets and account management.

How Does SSO Work?

SSO relies on a trust relationship between a central identity provider (IdP) and the applications your business uses (known as service providers). Here is the typical flow:

1. A user opens a business application (e.g., their CRM or project management tool)
2. The application redirects the user to your organisation's identity provider
3. The user signs in with their credentials (and completes MFA if enabled)
4. The identity provider confirms the user's identity and sends an authentication token to the application
5. The application grants access — no separate login required

If the user then opens another SSO-connected application during the same session, they are automatically authenticated without needing to log in again. The identity provider handles everything behind the scenes.

Common SSO Protocols

SSO uses industry-standard protocols to securely exchange authentication data between the identity provider and applications:

• SAML 2.0 — The most widely used protocol for enterprise SSO, commonly used with Microsoft Entra ID and Okta
• OpenID Connect (OIDC) — Built on top of OAuth 2.0, popular with modern web and mobile applications
• OAuth 2.0 — Primarily an authorisation protocol, often used alongside OIDC for access control

You do not need to understand the technical details of these protocols. Your identity provider and applications handle the integration automatically.

Benefits of SSO for Business

Implementing SSO delivers tangible benefits across security, productivity, and IT operations:

Stronger Security

• Fewer passwords mean fewer risks — Users are less likely to reuse weak passwords or write them down
• Centralised access control — IT can revoke access to all applications instantly when an employee leaves
• MFA at the front door — Apply multi-factor authentication once at the identity provider level, protecting every connected application
• Reduced phishing surface — Users only enter credentials on one trusted login page, making phishing attempts easier to spot

Improved Productivity

• No more password fatigue — Staff spend less time logging in and resetting forgotten passwords
• Seamless app switching — Move between tools without interruption
• Faster onboarding — New employees get access to all their apps through a single account setup

Easier IT Management

• Fewer helpdesk tickets — Password resets account for a significant portion of IT support requests. SSO dramatically reduces these
• Central user management — Add, modify, or remove user access from one dashboard
• Better compliance — Audit logs and access reports are consolidated in one place

SSO and Zero Trust Security

SSO is a key enabler of zero trust security. By centralising authentication through a single identity provider, businesses can enforce consistent security policies — including MFA, device compliance checks, and conditional access rules — across every application.

Rather than trusting users simply because they are on the corporate network, zero trust with SSO verifies identity at every access point.

Popular SSO Solutions for UK Businesses

Several identity providers offer SSO capabilities suitable for businesses of all sizes:

• Microsoft Entra ID (formerly Azure AD) — Included with Microsoft 365 Business Premium. Integrates natively with thousands of applications
• Okta — A dedicated identity platform with extensive app integrations and strong conditional access features
• Google Workspace — Provides SSO for businesses using the Google ecosystem
• JumpCloud — A cloud directory that combines SSO, device management, and MFA in one platform
• OneLogin — An affordable SSO solution with a focus on ease of deployment

For businesses already using Microsoft 365 Business Premium, Microsoft Entra ID is often the most natural starting point — it provides SSO, MFA, and conditional access without additional licensing costs.

Is SSO Right for Your Business?

SSO is worthwhile for almost any business using more than a handful of cloud applications. It is particularly valuable if:

• Your team regularly forgets passwords or raises helpdesk tickets for resets
• You need to meet compliance requirements like Cyber Essentials, ISO 27001, or GDPR
• Employees work remotely or across multiple devices
• You are onboarding and offboarding staff frequently
• You want to strengthen security without adding friction for users

For organisations with managed IT support, SSO deployment is typically handled as part of the service — from initial setup through to ongoing user management.

If you are considering SSO for your business, a managed IT provider can assess your current setup, recommend the right identity platform, and handle the migration.