What is a Combo Chart in Excel?

A combo chart in Excel is one of the most practical tools for telling a clear story with your data, especially when you're working with different types of information at once. It lets you layer two different chart types, like columns and a line, on top of each other to show different kinds of data in a single visualization. This article will walk you through exactly what a combo chart is, why it's useful, and how to create and customize one step-by-step.

What Is a Combo Chart and Why Is It Used?

A combination chart, or "combo chart," combines two or more chart types into a single chart. The most common pairing is a column chart with a line chart. This is incredibly useful in a few key scenarios:

• When you have mixed data types. For example, you might want to show total sales revenue (a high number, in currency) alongside the number of units sold (a lower number) for each month.
• When your data uses wildly different scales. Imagine plotting website traffic (in the tens of thousands) and the conversion rate (e.g., 2.5%) on the same axis. The conversion rate line would appear completely flat and useless near the zero line. A combo chart solves this by adding a secondary axis, giving each data series its own scale to live on.
• When you want to compare a value against a target or average. A classic example is showing actual monthly sales as columns while overlaying a sales target as a single horizontal line.

In short, combo charts help you show relationships between different metrics that would be difficult or impossible to see with separate charts. They save space on your dashboard and make complex data much easier for your audience to understand at a glance.

How to Create a Combo Chart in Excel: A Step-by-Step Guide

Creating a combo chart is straightforward once you know the steps. Let's build one using a typical business example: tracking monthly sales revenue and the number of units sold.

Step 1: Set Up Your Data Table

First, organize your data into a clean table. Make sure each column has a clear header. For our example, the data structure looks like this:

|   Month   | Revenue ($)   | Units Sold  |
|-----------|---------------|-------------|
| January   |    $12,000    |     240     |
| February  |    $15,500    |     310     |
| March     |    $18,000    |     360     |
| April     |    $16,200    |     324     |
| May       |    $21,000    |     420     |
| June      |    $25,300    |     506     |

Notice how "Revenue" is in the tens of thousands, while "Units Sold" is in the hundreds. This is a perfect scenario for a combo chart with a secondary axis.

Step 2: Select Your Data

Click and drag your cursor to highlight the entire range of data you want to include in the chart, including the column headers. For our table, you would select cells A1 through C7.

Step 3: Insert the Chart

With your data selected, navigate to the Excel ribbon at the top of the screen.

1. Click on the Insert tab.
2. In the Charts group, find and click the "Insert Combo Chart" icon. It looks like a small bar chart with a line chart overlaid on it.

A dropdown menu will appear with a few default options.

Step 4: Choose the Right Combo Chart Type

Excel gives you three main choices here:

• Clustered Column - Line: This is the default. It plots both data series on the same primary vertical axis. This works fine if your data series have similar scales, but it isn't right for our example.
• Clustered Column - Line on Secondary Axis: This is exactly what we need. It will plot one series (Revenue) as columns using the primary axis on the left, and the other series (Units Sold) as a line using a new secondary axis on the right.
• Create Custom Combo Chart...: This option gives you full control. Clicking gives you a dialog box where you can manually assign a chart type and axis to each data series.

For our example, choose Clustered Column - Line on Secondary Axis. Excel will instantly generate the chart for you. You should now see blue bars representing revenue (read off the left axis) and an orange line representing units sold (read off the right axis).

Customizing and Formatting Your Combo Chart for Clarity

A basic chart is good, but a well-formatted chart is great. Taking a few extra minutes to clean up your combo chart will make it far more powerful and professional.

Add Descriptive Titles and Axis Labels

Clear labels are non-negotiable. If your audience has to ask "What am I looking at?" your chart has failed.

• Chart Title: Click on "Chart Title" at the top and give it a specific name, like "Monthly Sales Revenue vs. Units Sold."
• Axis Titles: This is critical for combo charts. You need to label both the primary and secondary vertical axes.

Adjust the Axes Scale

Sometimes, Excel’s default axis scales don't highlight the story you want to tell. You might want to change the minimum or maximum values.

1. Right-click the axis you want to change (for example, the left vertical axis).
2. Select Format Axis.
3. In the pane that appears, you can manually set the Bounds (Minimum and Maximum) for that axis. For example, if your smallest revenue value is $12,000, you might set the minimum bound to $10,000 to better focus on the variation in the columns.

Format the Data Series

Making your chart visually appealing helps it land with your audience. You can change colors, line styles, and more.

• Changing Colors: Right-click on one of the columns or the line and select Format Data Series. Use the paint bucket icon to choose a new fill or line color. Stick to brand colors or a simple palette that provides good contrast.
• Changing the Line Style: To make a target line stand out, you can change its style. In the "Format Data Series" pane for the line, you can change the dash type from solid to dotted.

Add Data Labels for Precision

For presentations, it's often helpful to show the exact values directly on the chart.

1. Right-click on the data series (either the columns or the line).
2. Select "Add Data Labels".
3. Excel will place the values directly on the chart. You can then click on a data label to format its position, font size, or number format.

Practical Examples of Combo Charts in Business

Now that you know the mechanics, let's look at a few more common business scenarios where combo charts shine.

P&L Statement: Revenue vs. Gross Margin Percentage

You can visualize monthly total revenue as columns and the gross margin percentage (profitability) as a line. This quickly shows whether high-revenue months are also your most profitable months.

Website Analytics: Sessions vs. Goal Conversion Rate

Show the total number of website sessions per day as columns, with the goal conversion rate (e.g., newsletter signups) as a line. You can spot if a big spike in traffic actually led to more conversions or if it was low-quality traffic.

Inventory Management: Units on Hand vs. Price per Unit

For a product, you could plot the number of units in inventory in a given month (columns) against the average selling price (line). This might reveal pricing trends related to stock levels.

Common Mistakes to Avoid

Combo charts are amazing, but they can be misleading if used poorly. Here are a few things to watch out for:

1. Forgetting to Label the Secondary Axis: This is the most common mistake. Without a clear label on the right-hand axis, your line chart is meaningless and your audience will be completely lost.
2. Over-Cluttering the Chart: Don't try to cram too much information into one chart. A combo chart works best with two, or at most three, data series. Any more becomes a visual mess.
3. Using Unrelated Data: Only combine data series that have a logical relationship. Plotting "Customer Support Tickets" against "Office Coffee Consumption" probably isn't going to provide a meaningful insight.
4. Misleading Axis Scales: Be careful not to manipulate the axis scales to exaggerate a trend. For example, setting the minimum of a vertical axis just below your lowest value can make small variations look like massive swings.

Final Thoughts

Mastering the combo chart in Excel is a fantastic way to elevate your data reporting. By combining columns and lines on primary and secondary axes, you can tell a more nuanced story and reveal relationships in your data that a simple bar chart or line graph could never show on its own.

Building these reports manually in Excel or Google Sheets gives you a lot of control, but it still takes time to connect your data sources, build the charts, and format them every reporting period. If you want to get these kinds of insights instantly, that's what we built Graphed for. You can connect all your platforms - like Google Analytics, Shopify, HubSpot, or even a Google Sheet - and just ask for what you need in plain English. For example, you could say, "Create a dashboard showing our monthly revenue as a bar chart and our conversion rate as a line chart," and it builds a live, interactive visualization for you in seconds.