SharePoint Site vs Site Collection: Understanding the Key Differences

If you're navigating the architecture of SharePoint, one of the most important concepts to grasp is the distinction between a site and a site collection. While these terms may sound similar, they represent different levels of organization within SharePoint and play distinct roles in governance, permission management, and content structure.

In this article, we'll explore the definitions, differences, use cases, and best practices for working with SharePoint sites and site collections.

What Is a SharePoint Site?

A SharePoint site is a single, self-contained workspace within a SharePoint environment. It typically serves as a collaboration hub for a team, department, or project. Each site can host content such as document libraries, lists, pages, calendars, tasks, and apps. Users can customize the site layout, add web parts, and define workflows that suit their business needs.

In modern SharePoint Online (Microsoft 365), every time you create a Microsoft 365 Group, Team in Microsoft Teams, or a Communication Site, a SharePoint site is provisioned behind the scenes.

There are two primary types of SharePoint sites:

• Team Sites – Designed for internal collaboration with Microsoft 365 groups, allowing members to co-author documents and share updates.
• Communication Sites – Meant for broadcasting information to a broader audience with a more polished, publishing-focused layout.

Each site has its own unique URL, permission settings, and content libraries, making it suitable for specific business contexts.

What Is a SharePoint Site Collection?

A site collection is a logical grouping of one or more SharePoint sites under a single top-level site. It acts as the highest level of organization in the SharePoint hierarchy. Within a site collection, there is:

• A top-level site, which serves as the parent
• One or more subsites, each with its own permissions, content, and features

All sites in a site collection share a common infrastructure:

• Same database (in classic environments)
• Unified site columns and content types
• Consistent branding and navigation (if configured)
• Shared storage quota and usage metrics

In classic SharePoint environments (on-premises and legacy SharePoint Online), site collections were used to define boundaries for administration and data isolation. Each site collection was a unit of management: separate search scopes, permission inheritance boundaries, and backup/restore entities.

The Evolution in SharePoint Online

With the rise of modern SharePoint Online, Microsoft has shifted from subsites within site collections to a flat architecture. Today, the best practice is to create multiple site collections (each as a top-level modern site) and connect them via Hub Sites for navigation and organizational cohesion.

This flat model offers several advantages:

• Greater flexibility in permissions and governance
• Easier migration and scalability
• Independent site lifecycle and sharing settings
• Avoidance of tight coupling between departments or teams

In modern SharePoint, every site—whether it's a team site or communication site—is effectively its own site collection.

Key Differences Between a SharePoint Site and Site Collection

While a SharePoint site is a workspace where users collaborate and store content, a site collection is a container for one or more sites. Think of it like this: a site is an office room, while a site collection is the entire office building.

Each site can have its own unique permission settings, design templates, and content types, but when part of a site collection, they still share higher-level configurations.

A site collection defines a boundary for settings and features that cannot span across collections. For instance:

• A content type defined in one site collection isn't automatically available in another
• Permissions cannot be inherited between different site collections
• Search scopes and audit logs are typically confined within a site collection
• Backup and restore operations are performed at the site collection level

Governance and Permission Management

From a governance perspective, site collections offer a convenient way to segment administrative responsibilities. You can assign different site collection administrators for different parts of your organization, allowing decentralized control while maintaining data boundaries.

Each site within a collection can have its own unique set of members and permission levels, but subsites within a site collection often inherit permissions from the parent site unless specifically broken.

In modern SharePoint, where each site is its own site collection, site owners manage permissions directly through Microsoft 365 Groups, making it simpler and more user-friendly.

When to Use a SharePoint Site

Use a standalone SharePoint site when:

• You need a simple, dedicated workspace for a team or project
• Collaboration is limited to a small group of users
• You are using Microsoft Teams or Planner, as they auto-create a SharePoint site
• You want to leverage modern features like document co-authoring, Lists, and web parts

When to Use a SharePoint Site Collection

Use a site collection when:

• You need separate administrative and security boundaries
• You require independent quotas, audit logs, and retention policies
• You're working with legacy SharePoint structures with subsites
• You want to manage branding or feature availability at a higher level

In modern SharePoint, this is often automatic, as each new site is also a new site collection.

Moving Toward Modern Site Architecture

If you're still relying heavily on subsites within site collections, consider modernizing to a flat architecture using Hub Sites. Hub Sites provide a way to:

• Group related sites without nesting them
• Share branding and navigation across sites
• Create a unified search experience
• Maintain flexibility in site ownership and lifecycle

This modern structure is more aligned with Microsoft’s direction for SharePoint Online and better supports agile, decentralized content management.

Conclusion

Understanding the difference between a SharePoint site and a site collection is key to building an effective and scalable SharePoint environment. A site is a functional workspace for teams and content, while a site collection is the structural container that governs those sites.

As Microsoft continues to emphasize modern, flat architecture, it's becoming best practice to treat each site as its own site collection and use Hub Sites for connectivity and cohesion. This approach enhances flexibility, simplifies management, and future-proofs your SharePoint implementation.

Frequently Asked Questions (FAQs)

1. Can a SharePoint site exist without a site collection?

No. Every SharePoint site must exist within a site collection. In modern SharePoint Online, each site (Team or Communication) is effectively the root of its own site collection, even if it appears as a standalone site to the user.

2. What is the main advantage of using a flat site architecture in SharePoint Online?

Flat architecture simplifies permission management, improves scalability, and aligns with Microsoft’s modern SharePoint framework. It avoids deep subsite hierarchies and enables flexibility by allowing sites to be independently managed and connected via Hub Sites.

3. Can you convert a subsite to a top-level site collection in SharePoint Online?

Not directly through the SharePoint admin interface. However, you can migrate a subsite into a new site collection using tools like SharePoint Migration Tool (SPMT), PowerShell scripts, or third-party solutions like ShareGate or AvePoint.

4. Is it possible to share content between different site collections?

Yes, but sharing between site collections requires more deliberate configuration. Unlike subsites within a site collection, different site collections do not inherit permissions or navigation. You can enable external sharing, use OneDrive links, or integrate content via Hub Sites or Microsoft Search.

5. How many site collections can I have in SharePoint Online?

As of the latest limits, SharePoint Online allows up to 2 million site collections per tenant. Each site collection can support its own storage, users, and configuration. This scalability is ideal for enterprise-grade deployments.

6. Can subsites still be created in SharePoint Online?

Yes, subsites can still be created in classic SharePoint sites or through the "Subsite" option if it’s enabled. However, Microsoft recommends avoiding subsites in favor of modern, standalone sites connected by Hub Sites for better flexibility and long-term sustainability.

7. What happens when I delete a site collection?

Deleting a site collection in SharePoint Online removes the root site and all associated content, subsites (if any), lists, libraries, and pages. However, the deleted site collection is moved to the SharePoint Recycle Bin, where it can be restored within 93 days.

8. How are permissions managed across site collections vs. within a site?

Permissions in a site collection are managed independently. Each site collection has its own unique permission structure. Within a site (especially subsites), permissions can be inherited or broken depending on your access control needs.