BPMN Gateways: Understanding Types and Best Practices
In the world of business process modeling, BPMN gateways play a crucial role in controlling the flow between activities. They represent divergence points in the process — such as decisions, parallel paths, or event-based waits — and are essential for creating clear, logical, and efficient process flows.
In this article, you’ll learn about the main types of BPMN gateways, when to use each one, and best modeling practices based on expert guidance from BPMN Method and Style by Bruce Silver.
What Are BPMN Gateways?
In BPMN (Business Process Model and Notation), a gateway is represented by a diamond shape and is used to determine how the process flow will proceed at a given point. Gateways can:
- Direct the flow into one or more paths (divergence)
- Wait for multiple paths to join (convergence)
- React to external events (such as messages or timers)
Types of BPMN Gateways
BPMN provides several types of gateways to represent different ways a process can branch or merge. Each type has specific behavior and use cases, making it important to choose the right one based on the flow logic you need to model.
Also, all gateways are visually represented by a diamond shape, with a distinct marker in the center to indicate the gateway type.
Exclusive Gateway (XOR)
The Exclusive Gateway allows the process to follow only one path based on a condition. It is commonly used for decision points such as “approved” or “rejected,” and it does not require synchronization afterward.
Visually, it is represented by a diamond with an “X” symbol in the center.
Inclusive Gateway (OR)
The Inclusive Gateway enables the process to follow one or more paths simultaneously, depending on which conditions are satisfied. It’s useful for scenarios where multiple outcomes can occur at once, and it requires synchronization when merging paths that end with triggered events.
This gateway is drawn as a diamond containing a circle in the middle.
Parallel Gateway (AND)
The Parallel Gateway triggers all outgoing paths at the same time, regardless of any conditions. It’s ideal for executing independent tasks in parallel and typically requires synchronization at the point where the paths converge again.
It is visually identified by a diamond with a plus sign (+) in the center.
Event-Based Gateway
This gateway waits for external events to occur — such as receiving a message or a timer expiring — and proceeds along the path associated with the first event that happens. It's especially useful in event-driven scenarios.
Its visual representation is a diamond with a thin-lined circle, often containing an event marker like a clock or envelope.
Complex Gateway
The Complex Gateway supports advanced control flow logic, allowing configurations such as “wait for any two of the following branches” or other custom patterns that can’t be modeled with basic gateways.
It is depicted as a diamond with an asterisk (*) symbol inside.
Synchronization and BPMN Gateway Best Practices
When using gateways in BPMN, it’s important to understand whether the flows you diverge need to be synchronized before continuing the process. This depends on the type of gateway used and how the process ends.
Let’s clarify this with a practical comparison:
🔄 Parallel Gateway: Synchronization Required
When you use a Parallel Gateway to split the process into multiple branches, all paths will run simultaneously. If these branches need to come back together later, you should use another Parallel Gateway to synchronize them — especially if the process ends with a trigger (like a message, signal, or escalation).
Example:
“Send welcome email” and “Create user account” run at the same time. Both must finish before continuing to “Finish onboarding”.
- ✅ Requires synchronization with another Parallel Gateway
- ✅ Ensures that both branches have completed before continuing
❌ Exclusive Gateway: Synchronization Not Needed
An Exclusive Gateway, on the other hand, allows only one path to be followed. Since the other paths are not activated, there’s nothing to synchronize later on.
Example:
After reviewing a purchase request, the process goes either to “Place purchase order” or “Request cancelled,” but never both.
- ❌ No need for a joining gateway
- ✅ The process can continue naturally from each path
🟡 Important Exception
Even when using Parallel or Inclusive Gateways, synchronization may not be necessary in some cases.
According to Bruce Silver’s BPMN Method and Style, if each path ends with a simple End Event (i.e., an end with no trigger), then synchronizing the branches is not required.
This applies when the parallel flows are meant to terminate independently and no further action depends on all of them finishing.
But if any End Event includes a trigger, then synchronization is necessary to avoid multiple unintended triggers.
Now that you understand the logic behind synchronization, here’s a summary table with recommendations based on Bruce Silver’s methodology:
| Gateway Type | Ends with simple End Event | Ends with End Event with trigger | Synchronize? |
|---|---|---|---|
| Exclusive (XOR) | ❌ No | ❌ No | Never needed |
| Inclusive (OR) | ❌ No | ✅ Yes | Depends on the End Event |
| Parallel (AND) | ❌ No | ✅ Yes | Depends on the End Event |
| Event-Based (XOR) | ❌ No | ❌ No | Never needed |
🧠 Practical Example of BPMN Gateways
This BPMN diagram for travel requests is a great example to illustrate how different gateway types can be applied in real-life business processes.
✅ Exclusive Gateway (XOR) — for decision-making
The first gateway encountered in the process is an Exclusive Gateway. It is used after the travel request has been reviewed. Only one outcome is possible:
- If the travel request is approved, the process continues.
- If it is rejected, the process ends with a cancellation notice.
This is a classic example of using a XOR gateway to control the flow based on a business rule or condition.
🔄 Inclusive Gateway (OR) — for multiple simultaneous needs
Once the request is approved, the process reaches an Inclusive Gateway. At this point, the system evaluates what arrangements are needed:
- Booking airline tickets
- Booking accommodation
- Both
Depending on what’s required, one or both of these flows are activated.
Later, these paths are synchronized by a second Inclusive Gateway ("Finalize Travel Details"), ensuring that all necessary tasks are completed before moving on.
This demonstrates the correct use of an inclusive gateway pair — where you split into multiple conditional branches and must synchronize them before continuing, especially when more than one branch may be active.
You can open and explore this BPMN diagram completely free using a free account on the HEFLO BPMN Modeler. Click the button below to view and edit the diagram directly in your browser:
🎓 Creating Your First BPMN Diagram with an Exclusive Gateway
As part of our free BPMN modeling class, we guide you in creating your first BPMN diagram — and it includes an Exclusive Gateway.
What you’ll learn:
- How to set up a basic BPMN process with a Start Event and tasks
- When and why to use an Exclusive Gateway for decision logic
- How to model branching flows using simple yes/no conditions
- Labeling best practices for clarity and maintainability
This hands-on experience is perfect for beginners who want to understand process modeling through real use cases.
📚 Recommended Reading: BPMN Method and Style by Bruce Silver
If you want to deepen your understanding of BPMN beyond the basics, we highly recommend the book BPMN Method and Style by Bruce Silver. In our opinion, it is the most complete and practical reference for anyone who wants to model business processes with clarity, precision, and consistency.
Key topics include:
- All BPMN elements explained, including gateways, events, and subprocesses
- Common modeling mistakes and how to avoid them
- Best practices for collaboration diagrams and executable processes
- Guidelines for readable, consistent diagrams that follow a structured methodology
Where to buy
You can purchase the book from several popular platforms:
- 📘 Amazon (paperback or Kindle): Search here
- 📗 Barnes & Noble: barnesandnoble.com
- 📕 Official site: methodandstyle.com — includes training and templates
✨ Conclusion
Understanding BPMN gateways is essential for any professional working with process automation, continuous improvement, or business workflow design. When used correctly, each gateway type contributes to a clearer, more precise, and execution-ready process model.
