How to Merge Two Visualizations in Power BI

Combining two visualizations into a single chart can instantly reveal relationships in your data, like showing how marketing spend impacts sales revenue over time. This skill moves you from creating basic charts to building an insightful, analytic dashboard. This tutorial will walk you through how to merge visualizations in Power BI, focusing on the most common and effective method: the combo chart.

Why Merge Visualizations in the First Place?

Before diving into the “how,” let’s touch on the “why.” When you combine visuals, you’re not just saving space on your report canvas - you’re telling a more sophisticated story with your data. The goal is to show a direct relationship between two or more different metrics within the same context, usually a shared time period or category.

Here are a few common scenarios where merging visuals is incredibly powerful:

• Tracking Volume vs. Value: Show the number of units sold (columns) against the total revenue generated (line). This can help you see if you're selling more low-value items or fewer high-value ones.
• Correlating Activities and Outcomes: Plot advertising spend (columns) against website sessions or leads generated (line). This quickly shows if your ad budget increases are leading to proportional traffic growth.
• Comparing Actuals vs. Targets: Display actual sales performance (columns) overlaid with a sales target or quota (line). This is a classic management visual for tracking progress towards goals.
• Monitoring Efficiency: Combine total orders (columns) with the average order value (line) to see if promotional campaigns are driving more transactions, but at a lower per-order value.

In all these cases, merging the two pieces of information into one chart makes the connection immediate and easy to understand, saving your audience from having to mentally connect dots between two separate graphs.

The Easiest Method: Creating a Combo Chart

The most straightforward and officially supported way to merge visuals in Power BI is by using the built-in "combo chart" visual types. Power BI offers two main options: the Line and stacked column chart and the Line and clustered column chart. For this tutorial, we’ll use the Line and stacked column chart, but the steps are nearly identical for both.

Let's create a chart that shows monthly sales revenue (in columns) and the average customer satisfaction score (as a line).

Step 1: Get Your Data Ready

For any combo chart to work, you need three key ingredients:

1. A shared category or time series to plot on the x-axis (e.g., month, product category, region).
2. A numeric value to display as columns (e.g., Total Revenue).
3. A second numeric value to display as a line (e.g., Customer Satisfaction Score).

Make sure your data model includes these fields. For our example, we'll assume we have a table with a 'Date' column, a 'Sales Amount' column, and a 'CSAT Score' column.

Step 2: Add the Combo Chart to Your Report

In your Power BI report view, navigate to the Visualizations pane on the right-hand side. Find the icon for the Line and stacked column chart and click it to add it to your report canvas.

You'll see a blank visual placeholder appear. Now it's time to populate it with data.

Step 3: Configure the Chart Fields

With the new blank chart selected, look at the field wells under the Visualizations pane. This is where you tell Power BI what data to put where.

• Shared X-axis: Drag your shared category or date field here. We'll drag our 'Month' column into the X-axis field.
• Column Y-axis: Drag the measure you want to see as columns here. We'll drag 'Sales Amount' to the Column Y-axis field.
• Line Y-axis: Drag the measure for your line graph here. We’ll drag 'CSAT Score' to the Line Y-axis field.

As soon as you populate these fields, Power BI will render a combined chart. You'll see columns representing your monthly sales and a line layered over them showing the trend in customer satisfaction scores.

Step 4: Formatting for Clarity (The Crucial Step)

A functional chart is great, but a clean, well-formatted one is better. When combining two different measures, the scales are often very different. For example, Sales might be in the hundreds of thousands, while your CSAT Score might be a number between 1 and 5. This will squash your line chart flat against the x-axis, making it unreadable.

This is where the secondary Y-axis becomes your best friend.

Enable and Format the Secondary Y-Axis

1. Select your chart.
2. Click the paintbrush icon in the Visualizations pane to open the Format your visual tab.
3. Expand the Secondary Y-axis section.
4. Toggle the switch to On.
5. Power BI automatically moves your line chart's values to this new axis on the right side of the visual. Voila! Both visualizations are now clearly visible and scaled appropriately.

While you're in the formatting pane, take a moment to improve your chart even more:

• Colors: Under the 'Columns' and 'Lines' sections, choose distinct, complementary colors to make the visual easy to interpret.
• Data Labels: Consider turning on data labels if you want to show the exact values for each column or data point on the line. But be careful not to clutter the visual.
• Titles and Legends: Go to the 'General' tab and update the Title to be descriptive, like "Monthly Revenue vs. Customer Satisfaction Score." Ensure the legend is enabled and clearly labels the columns and the line.

Alternative Techniques for Combining Visuals

While the combo chart is the workhorse, there are other creative ways to combine visual information in Power BI.

1. Small Multiples: Compare Trends Across Categories

This feature isn't about overlaying two visuals, but it's a fantastic way to combine them by splitting one chart into multiple smaller ones based on a category. This allows for quick, like-for-like comparisons.

For example, you could see your "Revenue by Month" line chart repeated for each product category.

How to set it up:

1. Create a standard line chart (e.g., Total Sales by Month).
2. Drag a categorical field (like 'Product Category' or 'Region') into the Small multiples field well in the Visualizations pane.
3. Power BI will instantly create a grid of mini-charts, making it easy to spot which categories are over- or under-performing.

2. The Scatter Chart: Show All Your Data Points

A scatter chart is fundamentally designed to show the relationship between two numerical measures. By incorporating a time dimension, you can effectively "merge" trend analysis with correlation.

Imagine you want to see if there's a relationship between the number of discounts given and overall profit on each day of the month.

How to set it up:

1. Add a Scatter chart visual to your report.
2. Drag 'Number of Discounts' to the X-axis.
3. Drag 'Profit' to the Y-axis.
4. Drag your 'Date' field to the Values field. This creates a dot for each day.
5. Go to the Analytics pane (the magnifying glass icon) and add a Trend line. This overlays a line showing the general correlation, merging the high-level trend with the granular daily data points.

Final Thoughts

Combining visualizations in Power BI, particularly with combo charts, is a core skill for building reports that do more than just present numbers - they provide context and reveal patterns. By layering data sets, you can show direct relationships, compare performance against goals, and tell a much richer story in a fraction of the space.

The manual process in tools like Power BI gives you granular control, but it involves several clicks and a solid understanding of field wells and formatting options. At Graphed, we simplified this process entirely. You can connect your data and just ask a question like, "Show me my total sales as a column chart and my average lead score as a line chart by month." Our AI data analyst builds the real-time combo chart for you in seconds - no dragging, dropping, or configuring a secondary axis required.