What Single Sign-on Means for Your Own Applications

“Single sign-on” essentially means that users sign in once and can then use several connected applications without having to sign in separately again.

For companies using Microsoft 365, this is particularly relevant when in-house applications need to work alongside Teams, SharePoint or other internal systems. In that case, it is not just about convenience, but also about clear processes, user acceptance and a coherent application landscape.

This article therefore does not cover the technical setup in detail, but rather the practical context for decisions, processes, security and project planning. If you would like to assess your own project afterwards, ballmüller solutions’ services, the cost calculator, the project check, contact and a no-obligation initial consultation, reference projects and client testimonials and another article on SaaS will help.

What Single Sign-on Means in Practice

In day-to-day use, single sign-on means this: a central sign-in service confirms who a user is, and connected applications adopt that sign-in. Once someone has signed in successfully, they can then use several systems without having to log in separately to each application.

Without single sign-on, each application usually has its own user management and its own sign-in screen. With single sign-on, access is bundled via a central identity. This creates a more consistent way in, even if several applications are working together in the background.

The term identity provider refers to the service that manages sign-ins and tells connected applications which user has signed in successfully.

For companies using Microsoft 365, this is especially relevant because the workplace sign-in is often already in place and can also be used for in-house applications. New web applications, portals or extensions do not then necessarily have to start with an additional, separate sign-in.

It is also important to distinguish this from passwords simply being saved in the browser. Single sign-on is more than convenience when filling in login fields. It means a systematic, central sign-in across connected applications.

Typical areas of use are:

• internal line-of-business applications
• customer portals and employee portals
• web applications
• mobile apps
• extensions in the Teams or SharePoint environment

Why This Matters for Companies Using Microsoft 365

For companies using Microsoft 365, single sign-on offers practical benefits above all in day-to-day work. Employees can get to their tasks more quickly if they do not have to re-enter their username and password for every line-of-business application. It may sound unspectacular, but it often makes workflows noticeably smoother.

It also makes it easier to start using new applications. If a solution works with the familiar company sign-in, the barrier to first use is usually lower. Users do not have to understand, manage or even request an additional account.

In day-to-day work, this also reduces the number of typical friction points:

• fewer separate logins
• fewer forgotten passwords
• less switching between different sign-in logic
• fewer breaks between systems

From an organisational point of view, one further aspect matters: a central identity makes access easier to manage. Permissions and sign-in rules need to be maintained in fewer places. This does not replace proper role planning, but it can improve clarity.

This is particularly relevant when roles change or when employees leave the company. If user accounts are adjusted internally, access to connected applications can be managed more systematically instead of having to maintain many individual solutions separately.

There is also a strategic point: with single sign-on, in-house applications feel less like isolated special solutions. They fit better into the existing working environment. Anyone who already works daily with Teams or SharePoint often expects exactly that: the same sign-in and access without additional hurdles.

This topic becomes especially important in hybrid system landscapes where standard software, in-house applications and interfaces come together.

Where Single Sign-on Makes Sense for In-house Applications

Single sign-on is especially useful where in-house applications are used regularly and form part of established workflows. Typical examples from a business perspective are:

• an internal portal
• a CRM
• a self-service area for employees
• an intranet module
• a mobile app for internal processes

The benefits become particularly clear in line-of-business applications where information from several sources comes together. When users switch between data, views and tasks, the sign-in should be as seamless as possible rather than becoming a repeated obstacle.

In the Microsoft Teams environment, this is often a decisive factor for user acceptance. If an application is available directly in the familiar working context and does not require a new sign-in, it is usually adopted more easily in everyday use.

The situation is similar with SharePoint. Extensions or connected applications feel more consistent for users if they tie into existing user accounts rather than appearing with their own separate access model.

Specific types of application also show this clearly: a CRM for an insurance broker benefits from a consistent sign-in because employees regularly work with sensitive customer information and clearly defined roles.

A web platform for local authorities that brings together sewer network data, condition information and planned measures gains clarity when different stakeholders can access the relevant areas through an organised sign-in.

Even a targeted extension between Azure DevOps and planning software shows that single sign-on is not only relevant for large portals, but also for individual integrations with a clearly defined purpose.

What Requirements and Limitations You Should Know

Entra ID is Microsoft’s service for identity and access management, which often forms the basis for single sign-on in the Microsoft environment.

What matters for context is this: single sign-on is not an end in itself. The effort is worthwhile mainly when an application is used regularly or is closely integrated into existing work processes. For rarely used one-off solutions, the benefit may be lower than for a portal, a line-of-business application or an extension closely tied to Teams.

It is just as important not to confuse sign-in with authorisation. Sign-in checks who a person is. Authorisation determines what that person is allowed to see, edit or approve in the application. So even with a shared sign-in, careful planning is still needed for

• which roles exist
• which areas are visible to whom
• which actions should be permitted

Not every existing software solution can simply be connected without further thought. Especially with older applications or third-party software, you need to check whether the architecture, interfaces and processes can actually support a sensible integration.

There are also organisational questions around data access, logging and role models. You should review such data protection and legal matters with your data protection officer or legal adviser.

Single sign-on also never affects only the login. It is part of an overall solution involving the application, interfaces, database and hosting.

How to Approach a Single Sign-on Project Properly

The starting point should not be the technology, but the usage context. First clarify: who is meant to use the application, in which workflow is it needed, and which existing Microsoft 365 services already play a role?

It is just as helpful to identify the target systems early on. These include, for example:

• Teams
• SharePoint
• internal databases
• interfaces to existing systems
• other portals or line-of-business applications

After that, you should structure the user groups and roles clearly. Management, specialist departments, internal employees, external partners or public authorities often have different access requirements. That is exactly what determines how sign-in, visibility and approvals should later be designed in a sensible way.

That is why it is important not to treat single sign-on as a technical detail left until the end. The sign-in and authorisation logic has an early impact on the functional concept, navigation, approvals and responsibilities.

For project planning, a clear process helps: first comes an initial discussion covering requirements, expectations and a rough estimate of the effort involved. This is followed by concept and design with a cost estimate. Then come development with regular coordination, quality assurance and go-live, followed afterwards by support and further development.

For an initial assessment, you can use the cost calculator. If your project is more complex, a project profile with follow-up questions and a cost range can be created from a description or a specification document.