Combo Charts in PowerPoint: How to Combine Chart Types for Better Insights

Dual-axis charts are the most misused visualization in business presentations. When someone pairs revenue bars with a margin percentage line, the secondary axis scale often distorts the relationship. A 2% margin change looks massive because the axis runs from 18% to 22%, while revenue appears flat on a zero-based scale. The visual correlation is misleading.

After auditing 150+ quarterly review decks, we found that roughly 40% of combo charts would have been clearer as two separate visualizations. The combo chart earned its place in only one scenario: when the relationship between metrics genuinely matters and the axes can be scaled honestly. Revenue and growth rate over time works. Revenue and customer satisfaction scores forced onto one chart rarely does.

This guide covers when combo charts genuinely outperform separate visualizations, how to build them in PowerPoint without creating accidental misinformation, and the axis scaling decisions that separate honest insights from misleading ones.

What Is a Combo Chart?#

A combo chart (also called a combination chart) displays two or more chart types in a single visualization. The most common combination pairs column or bar charts with line charts, allowing you to show different metrics on the same axis or on separate axes.

The power of combo charts lies in showing relationships between metrics that would otherwise require separate visualizations. Instead of two charts side by side, you get one integrated view where correlations become immediately visible.

When to Use Combo Charts#

Combo charts excel in specific scenarios where you need to visualize relationships between different types of data.

1. Comparing Trends with Different Units#

The classic use case: showing an absolute metric alongside a percentage or rate.

Examples:

• Revenue (dollars) with profit margin (percentage)
• Headcount (number) with attrition rate (percentage)
• Units sold (quantity) with average selling price (dollars)

2. Highlighting Volume vs. Efficiency#

When you need to show both how much and how well.

Examples:

• Sales volume with conversion rate
• Production output with defect rate
• Customer count with satisfaction score

3. Showing Cause and Effect#

When one metric might explain another.

Examples:

• Marketing spend (line) with resulting sales (bars)
• Training hours (bars) with productivity improvement (line)
• Temperature (line) with ice cream sales (bars)

4. Comparing Actual vs. Target or Budget#

When you need context for performance metrics.

Examples:

• Actual revenue (bars) with budget line
• Monthly costs (bars) with spending cap (line)
• Sales by rep (bars) with quota line

When NOT to Use Combo Charts#

Combo charts are not always the right choice. Avoid them in these situations:

The golden rule: if you cannot explain why the two metrics belong together in one sentence, they probably should not share a chart.

Types of Combo Charts#

PowerPoint supports several combo chart combinations. Here are the most useful for consulting presentations.

Column + Line (The Standard)#

The most common combo chart pairs clustered columns with a line. Columns show discrete values (typically the primary metric), while the line shows a trend or rate.

Best for:

• Revenue with growth rate
• Sales by category with overall average
• Monthly data with rolling trend

Visual characteristics:

• Columns occupy the primary axis (left)
• Line overlays the columns, often on secondary axis (right)
• Clear visual distinction between the two data types

Stacked Column + Line#

When your primary metric breaks into components, use stacked columns with a line overlay.

Best for:

• Revenue by segment with total growth rate
• Costs by department with margin percentage
• Sales by product with market share trend

Caution: This combination packs a lot of information. Use only when the audience needs to see both composition and trend simultaneously.

Clustered Column + Line#

When comparing multiple categories over time with an overlaid trend.

Best for:

• Comparing two competitors' sales with market total line
• Showing actual vs. budget bars with variance percentage line
• Multiple product lines with category average

Area + Line#

Less common but effective for showing cumulative effects with a rate overlay.

Best for:

• Cumulative revenue with growth rate
• Running total with threshold line
• Inventory levels with reorder point

Comparison Table: Combo Chart Types#

How to Create a Combo Chart in PowerPoint#

Follow these steps to create a professional combo chart in PowerPoint.

Step 1: Insert a Chart#

1. Click on the slide where you want the chart
2. Go to Insert > Chart in the ribbon
3. In the left panel of the Insert Chart dialog, select Combo
4. Choose a preset: Clustered Column - Line is the most common starting point
5. Click OK

Step 2: Enter Your Data#

PowerPoint opens an Excel-like spreadsheet for data entry.

1. Replace the sample data with your actual values
2. Column A: Categories (typically time periods like months or quarters)
3. Column B: First data series (will display as columns)
4. Column C: Second data series (will display as line)
5. Close the data window when finished

Step 3: Configure the Secondary Axis#

If your metrics have different scales:

1. Click on the chart to select it
2. Right-click on the line series
3. Select Format Data Series
4. Under Series Options, select Secondary Axis

The chart now displays two vertical axes—primary on the left, secondary on the right.

Step 4: Customize Chart Elements#

Add essential elements for clarity:

1. Click the + button (Chart Elements) next to the chart
2. Add:
   • Axis Titles — Label both the primary and secondary axes
   • Data Labels — Optional, for precise values
   • Legend — Essential for distinguishing series

Step 5: Format for Consulting Standards#

Apply professional formatting:

1. Remove gridlines — Click the gridlines and press Delete
2. Use high-contrast colors — Blue columns with orange line is a classic choice
3. Format axis numbers — Right-click axis, select Format Axis, adjust number format
4. Align chart title — Use an action title that states the insight

Best Practices for Combo Charts#

Creating a combo chart is straightforward. Creating one that communicates effectively requires attention to these principles.

Keep It Simple#

The greatest risk with combo charts is cognitive overload. Follow these rules:

• Limit to two chart types — Never combine three or more
• Limit to two data series per type — One or two column series, one line
• Remove decorative elements — No 3D effects, shadows, or gradients
• Use a clean color palette — Two contrasting colors maximum

Layer Thoughtfully#

The order of visual elements matters:

• Columns first, lines on top — Lines should overlay columns, not hide behind them
• Use transparency if needed — If columns obscure data points, reduce column opacity
• Ensure all data points are visible — Check that no values are hidden

Design for Dual Axes Carefully#

Dual-axis charts are controversial in data visualization because they can mislead. Follow these guidelines:

• Start both axes at zero — Unless you have a compelling reason not to
• Use consistent scaling logic — If one axis is 0-100, the other should not be 0-1000000
• Match axis ranges to data ranges — Avoid excessive white space above data
• Label axes clearly — Include units (%, $, units)
• Use color coding — Match axis label color to series color

Write Action Titles#

Generic titles like "Revenue and Growth" waste the headline. Write titles that state the insight:

Match Colors to Axes#

Help readers connect data to scales:

• Primary axis label and column series: Same color (e.g., blue)
• Secondary axis label and line series: Same color (e.g., orange)

This visual connection makes it immediately clear which axis corresponds to which data.

Common Mistakes to Avoid#

Mistake 1: Forcing Unrelated Metrics Together#

Just because two metrics can share a chart does not mean they should. Ask yourself: does seeing these together reveal an insight? If the answer is no, use separate charts.

Bad example: Customer count with office supply expenses Good example: Customer count with customer acquisition cost

Mistake 2: Misleading Dual-Axis Scales#

The most criticized aspect of dual-axis charts is the potential to manufacture false correlations by manipulating scales.

How it happens: By adjusting axis minimums and maximums, you can make any two lines appear to move together or apart.

How to avoid:

• Start both axes at zero
• Use scales that reflect actual data ranges
• Ask: would a different scale tell a different story? If yes, be cautious

Mistake 3: Too Many Data Points#

Line charts can handle 12-24 points (monthly data for 1-2 years). But combining with columns gets cluttered quickly.

Guidelines:

• 6-8 periods maximum for column + line combos
• For longer time series, consider a line-only chart
• Aggregate if needed (quarterly instead of monthly)

Mistake 4: Inconsistent Time Periods#

Both series must represent the same time dimension. Do not combine monthly columns with annual lines unless clearly labeled and intentional.

Mistake 5: Missing Axis Labels#

Without axis labels, readers cannot interpret values. Always include:

• Axis titles explaining what is measured
• Units (%, $M, units)
• Color-matched labels for dual-axis charts

Combo Charts vs. Other Chart Types#

When should you use a combo chart versus alternatives?

Advanced: Creating Combo Charts with Excel Links#

For consulting presentations where data updates frequently, linking your combo chart to Excel saves hours.

The Manual Method#

1. Create combo chart in Excel with your data
2. Copy the chart
3. In PowerPoint, use Paste Special > Paste Link
4. Chart updates when you refresh the link

Limitation: Links break when files move or rename.

The Add-in Method#

Add-ins like Deckary offer more robust Excel linking:

• Links survive file moves
• One-click refresh for all charts
• Cross-platform support (Windows and Mac)

For presentations with multiple combo charts requiring regular updates, add-in linking significantly reduces maintenance overhead.

Summary: Key Takeaways#

Combo charts are powerful when used correctly but can confuse or mislead when misapplied.

When to use combo charts:

• Comparing metrics with different units or scales
• Showing correlation between related metrics
• Visualizing actual vs. target or benchmark

When to avoid combo charts:

• Metrics are unrelated
• Dual axes could mislead
• Three or more chart types needed
• Audience unfamiliar with the format

Best practices:

• Limit to two chart types maximum
• Use high-contrast colors
• Label both axes clearly with units
• Match axis colors to series colors
• Write action titles that state the insight
• Start axes at zero to avoid misleading scales

Common mistakes:

• Forcing unrelated metrics together
• Manipulating scales to show false correlation
• Overcrowding with too many data points
• Missing axis labels

Combo charts solve a real problem: showing how different metrics relate across a common dimension. Use them when the relationship matters, format them for clarity, and your audience will understand complex data at a glance.

Related Guides#

• Waterfall Charts in PowerPoint — Create bridge charts showing change from start to end value
• Stacked Bar Charts in PowerPoint — Master part-to-whole visualizations and composition analysis
• How to Link Excel Charts to PowerPoint — Set up auto-updating charts that refresh with one click
• How to Present Data Effectively in PowerPoint — Consulting principles for executive-ready data visualization