How to Create a Sankey Diagram in Power BI?

A Sankey Diagram in Power BI is used to visualize how data flows between different stages, categories, or processes. It highlights the movement of resources, information, or values by using links whose width represents the magnitude of each flow.

Named after Irish engineer Matthew Henry Phineas Riall Sankey, this chart makes it easy to identify major contributors, bottlenecks, and drop-offs in a process.

In Power BI, Sankey diagrams help turn complex flow data into clear, interactive insights for faster decision-making.

Let’s dive right in.

What is a Sankey Diagram in Power BI?

Definition: A Sankey Diagram in Power BI is a flow chart that connects a source and a target to show how values move between them. Each connection (flow) represents a relationship between two points, and its width indicates the size or quantity of that flow.

This helps users analyze distribution, track transitions, and understand how data is split or combined across multiple stages.

Why Use a Sankey Diagram in Power BI?

Power BI Sankey diagrams are valuable for analyzing flows and understanding how data moves across different stages. They help businesses and analysts:

• Visualize complex flows: Show how data moves between categories, processes, or entities in a simple, intuitive way
• Highlight key paths: Use link width to reveal major contributors and high-impact flows instantly
• Identify inefficiencies: Spot bottlenecks, drop-offs, or resource losses that need attention
• Support better decisions: Provide clear insights that help analysts and stakeholders act quickly
• Enhance dashboards and reports: Create interactive, visually engaging Power BI reports for presentations and analysis

Data Requirements for a Sankey Diagram in Power BI

To create a Sankey Diagram in Power BI, your data must be structured to show the flow between two points. Each connection requires three key components:

Source

• The starting point of the flow (e.g., product, marketing channel, department, or process stage)

Target

• The destination where the flow moves (e.g., next stage in a funnel or outcome)

Value

• The quantity or volume of the flow (e.g., number of users, revenue, or units)

Example Data Structure

How to Create a Custom Sankey Diagram in Power BI?

This step-by-step guide shows how to build a clear and interactive Power BI Sankey Visual.

Step 1: Prepare Your Data

• Structure your dataset with three columns:
  • Source (From): Starting point of the flow
  • Target (To): Destination of the flow
  • Value (Weight): Flow size or volume

Tip: Ensure your data is clean, with consistent naming and no blank values, to avoid errors in the visual.

Step 2: Load Data into Power BI

1. Open Power BI Desktop
2. Go to Home → Get Data
3. Select your dataset (Excel, CSV, etc.)
4. Click Load

Step 3: Add a Custom Sankey Visual

1. Open the Visualizations pane
2. Click the three dots (…) → Get more visuals
3. Search for “Power BI Sankey Diagram” in AppSource
4. Select a custom Sankey visual and click Add

Step 4: Build the Sankey Visual

1. Drag the Sankey visual onto the canvas
2. Assign fields:
   • Source → Source field
   • Target → Destination field
   • Value → Weight field

Step 5: Customize the Chart

• Open the Format panel
• Adjust:
  • Colors for nodes and flows
  • Labels and tooltips
  • Node spacing and alignment

Step 6: Optimize Readability

• Limit the number of nodes to avoid clutter
• Use consistent colors for categories
• Avoid overlapping flows
• Keep flow direction clear (typically left → right)

Step 7: Add to Dashboard

• Resize and position the chart appropriately
• Combine with other Power BI visuals for context
• Save and publish your report

Native vs Custom Sankey Visuals in Power BI

Feature	Native Visuals	Custom Sankey Visuals
Availability	Built-in with Power BI	Must be added from AppSource
Supported Chart Types	Standard charts (bar, line, pie, matrix)	Sankey diagrams for flows between categories
Customization	Limited formatting	Node colors, flow thickness, labels, tooltips
Interactivity	Standard interactions	Interactive with hover effects and drill-through options
Maintenance	Fully supported by Power BI updates	Requires manual updates and compatibility checks
Use Case	Simple charts and reports	Visualizing complex flows and relationships

Top 7 Use Cases for Power BI Sankey Chart

The Power BI Sankey chart is ideal for visualizing complex data flows. Common use cases include:

• Customer Journey

Track how customers move through marketing funnels, sales pipelines, or service stages to identify drop-offs and optimize experiences.

• Company Cash Flow

Show how money flows between accounts, departments, or projects to monitor inflows, outflows, and financial efficiency.

• Energy Flow

Visualize energy flow, consumption, and losses across systems to highlight inefficiencies and optimize usage.

• Supply Chain

Map the movement of materials from suppliers to delivery to identify bottlenecks and improve operational efficiency.

• User Flow

Analyze how users navigate websites, apps, or platforms to enhance user experience and engagement.

• Funds Flow

Track the allocation and usage of funds across multiple projects or departments for better transparency and control.

• Data Lineage

Trace the movement of data between systems, tables, or reports to ensure accuracy, compliance, and effective governance.

When Not to Use a Sankey Chart in Power BI?

• When your data is simple: If the process has only a few steps or minimal movement, a basic bar, line, or column chart communicates insights more clearly.
• When flows overlap too much: This chart can become confusing if there are too many nodes or crossing connections, reducing readability.
• When exact values matter: Flow diagrams emphasize flow patterns and relationships, not precise numbers. Use tables or bar charts if your audience needs exact figures.
• When performance is a concern: Large datasets with many links can slow down Power BI visuals, making dashboards less responsive and harder to interact with.

Common Mistakes When Creating Sankey Charts in Power BI

• Using messy or inconsistent data

If your source and target names aren’t clean and consistent, the diagram will be inaccurate or fail to render properly.

• Too many nodes or links

Adding every possible category creates clutter and overlapping flows, making the chart hard to read.

• Ignoring data aggregation

Feeding raw transactional data without summarizing inflates connections and distorts the visual. Always aggregate flows at the right level.

• Incorrect field assignments

Placing the wrong field in Source, Target, or Value causes misleading relationships and invalid visuals.

• Skipping labels and tooltips

Without clear labels or tooltips, users can’t interpret what the flows represent, reducing their usefulness.

• Overcomplicating colors and styles

Using too many colors or inconsistent styles distracts viewers and masks insights. Stick to a simple, meaningful palette.

• Neglecting performance optimization

Large datasets without filtering or pre‑aggregation slow down Power BI, leading to lagging visuals or crashes.

Best Practices for Creating Sankey Diagrams in Power BI

• Keep Your Data Structure Clean

Ensure your Source, Target, and Value fields are well-organized. Accurate mapping helps the chart display flows correctly and prevents errors.

• Limit Unnecessary Nodes

Too many nodes can clutter the chart. Include only the key steps so the flow remains clear and easy to read.

• Use Consistent Colors

Apply colors that correspond to categories or stages. Consistent coloring helps users follow the movement through the chart without confusion.

• Highlight Key Paths

Adjust link thickness or colors to emphasize the most important flows. This makes insights easier to identify in dashboards and reports.

FAQs

How Do You Format Your Data to Build a Sankey Diagram in Power BI?

Structure your data into three columns: Source, Target, and Value. Each row should represent a connection between two points along with its flow size. Make sure the data is clean, consistent, and free of duplicates for accurate visualization.

Can Power BI create Sankey charts?

Power BI does not support Sankey charts natively, but you can easily create them using custom visuals from AppSource. These visuals allow you to display flows between categories with interactive and customizable features.

When should you use a Sankey diagram in Power BI?

Use a Power BI Sankey diagram when you need to visualize flows between categories, especially when tracking movement, transitions, or relationships in complex datasets.

Wrap up

Using the right visualization helps you communicate insights clearly, especially when you’re working with flows or connected stages. These charts are one of the most effective ways to show how values move across a process.

In this guide, we explored the Sankey diagram in Power BI from start to finish. We covered what it is, how it works, and how nodes and links represent the flow of data within a system.

We also looked at practical situations where this type of visual fits well, such as analyzing flows, relationships, and movement between stages.

To build a strong chart, the key points include:

• Limit the number of nodes and flows to maintain clarity
• Avoid using data where values are too similar to distinguish visually
• Focus on telling a clear and meaningful data story

Finally, we walked through how to create a Sankey chart in Power BI using custom visuals, along with best practices and common mistakes to avoid.

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• Creating a Hierarchy in Power BI
• Power of Business Intelligence Reporting