Create a Custom Combo Chart in Excel

To create a custom combo chart in Excel for Microsoft 365 on Windows, select your category labels and data series, then choose Insert > Insert Combo Chart > Create Custom Combo Chart. Assign a chart type to each series, turn on a secondary axis for a series with a different scale if needed, and select OK. A combo chart puts two chart types—such as columns and a line—in one chart so you can compare related measures more clearly.

What You’ll Need

Excel for Microsoft 365 on Windows, with your data arranged in a table or a simple rectangular range.
A category column, such as months, and at least two numeric data series you want to compare.
Clear series headers and consistent units within each series. For example, use monthly sales in dollars and a conversion rate in percentages.

For a running example, imagine columns labeled Month, Sales ($), and Conversion rate (%), with one row for each month. A column series can show sales, while a line series shows the conversion rate. The percentage may need a secondary axis because its scale is very different from the dollar values.

Step-by-Step

Prepare and select the data. Put category labels in the first column and each series in its own column, with a descriptive header in the top row. Keep the data contiguous, with no completely blank rows or columns inside the range. Include all headers and categories when selecting the range; for example, select the Month, Sales, and Conversion rate columns together. Do not include a totals row unless you specifically want that total plotted as another category.
Open the custom combo chart options. On the ribbon, select the Insert tab. In the Charts group, choose Insert Combo Chart, then choose Create Custom Combo Chart. If the button is not visible in your ribbon layout, use Insert > Recommended Charts, open the All Charts tab, and select Combo. The dialog lists each data series separately.
Choose a chart type for every series. In the combo dialog, use the chart-type dropdown next to each series name. For the example, choose Clustered Column for Sales and Line for Conversion rate. Excel lets you assign different types to different series; choose types that make the comparison easy to read. A line is often useful for a trend, while columns work well for values compared across categories.
Set the secondary axis where the scales differ. In the same dialog, select the Secondary Axis checkbox for Conversion rate if plotting it against the dollar scale would make its line appear nearly flat. Leave it unchecked when the series share a meaningful scale and unit. Click OK to insert the chart. Excel displays a second value axis, typically on the right, for a series assigned to it.
Check that Excel interpreted the data correctly. Look at the chart to confirm that the months appear along the horizontal axis and that the intended series have the correct chart types. If Excel has treated months as separate series or plotted the headers as data, select the chart and choose Chart Design > Switch Row/Column. This changes how Excel reads the selected rows and columns; use it only if the current orientation is wrong.
Add a useful title and labels. Select the chart, then use Chart Design > Add Chart Element to add or edit a chart title, axis titles, and a legend as appropriate. Name the axes so readers know what each scale represents, such as Sales ($) on the left and Conversion rate (%) on the right. A title such as “Monthly Sales and Conversion Rate” explains the comparison more clearly than the default “Chart Title.”
Format the axes and series. Click an axis and right-click to choose Format Axis. Set number formatting and, when appropriate, sensible minimum and maximum bounds. For a percentage series, show percentage values on its secondary axis; for sales, use currency formatting on the primary axis. You can also right-click a series and choose Format Data Series to adjust its fill, line, markers, or gap width. Keep the two series visually distinct.
Review the result at its intended size. Make sure the legend identifies each series, both axes are understandable, and labels are not crowded. Resize the chart or move it to a chart sheet if it needs more room. If the source range will grow, consider converting it to an Excel table first with Insert > Table; charts based on a table can include newly added table rows. Save the workbook after checking the chart against the underlying values.

Common Mistakes

Using a secondary axis automatically: A second axis can make two scales readable, but it can also make a relationship look stronger or weaker than it is. Use it when the units or magnitudes differ, label it clearly, and avoid choosing limits that exaggerate small changes.
Combining unrelated measures: Putting unrelated series together does not make them meaningfully comparable. Use the chart to answer a specific question, and explain the measures with a clear title and axis labels.
Leaving headers out of the selection: Without headers, Excel may give series generic names or treat the first values as labels. Select the header row along with the data.
Choosing a confusing chart type: A pie or 3-D chart is rarely a good partner for a time-series column chart. Prefer a simple line-and-column combination and keep the number of series manageable.
Forgetting units and number formats: A secondary axis is not self-explanatory. Label it and format values as percentages, currency, or another appropriate number format.

Tips

Decide what comparison the chart should show before picking chart types. Use a line for movement over ordered categories and columns for values you want to compare side by side.
Use a secondary axis for a real scale problem, not just because the dialog offers one. If both series can be read clearly on one scale, one axis is often simpler.
Use restrained colors and a different visual treatment for each measure. For example, use one solid column color and a contrasting line with markers; do not rely on color alone if the chart may be printed in grayscale.
Keep category labels in chronological order. If months are sorted alphabetically, sort the source data into calendar order before creating or refreshing the chart.
When adding a new series, select the chart and use Chart Design > Select Data to review or change the chart’s data range. This is more reliable than dragging a selection over the chart.
In Excel for Mac, the chart tools and combo-chart options are available, but ribbon placement and dialog appearance can differ slightly by release. Use the Insert tab and look for the combo-chart option; Excel for the web may offer fewer chart-formatting controls, so open the workbook in the desktop app if a control is missing.

Troubleshooting

The combo option is missing or disabled. Confirm that you have selected a valid data range with at least two numeric series and category labels. If the ribbon is condensed, look under Insert > Recommended Charts > All Charts > Combo. A chart may also be unavailable for certain selections; try selecting the complete rectangular data range again.

The line is flat or hard to see. If the line’s values are much smaller than the columns, edit the chart type through Chart Design > Change Chart Type and assign that series to the secondary axis. Then format the secondary axis to match the series’ units. If the line still appears flat, check whether the source values are truly percentages or whether they were entered as whole numbers such as 25 instead of 25% (stored as 0.25).

The chart shows the wrong categories or series. Select the chart and choose Chart Design > Select Data. Check the chart data range, series names, series values, and horizontal category labels. Use Switch Row/Column if the data is being interpreted in the opposite direction. Make sure the source headers are text and the values are numeric rather than numbers stored as text.

New rows do not appear. Check whether the chart’s data range includes the added rows. If the source is an Excel table, add the new data directly below the table so it expands, then check that the chart includes it. For a normal range, go to Chart Design > Select Data and update the chart data range.

The chart looks misleading or cluttered. Remove unnecessary series or labels, simplify gridlines, and make both axes explicit. Compare the displayed axis bounds with the underlying values; a truncated axis can make changes look dramatic. If the chart needs too many scales or explanations, use two separate charts instead.

Frequently Asked Questions

What is a custom combo chart in Excel?
A combo chart displays two or more data series in one chart and lets you choose a chart type for each series. For example, one series can use columns and another a line.

Can I combine a column chart and a line chart?
Yes. In Create Custom Combo Chart, assign Clustered Column to one series and Line to another. You can choose whether the line uses a secondary axis.

When should I use a secondary axis?
Use one when series have different units or scales, such as dollars and percentages, and the smaller-scale series is difficult to see on the primary axis. Label the secondary axis with its unit and use appropriate limits.

Can I change a combo chart after creating it?
Yes. Select the chart and choose Chart Design > Change Chart Type to revise the chart type assigned to a series or its secondary-axis setting. Use Chart Design > Select Data to change the source range or series.

Why is my combo chart not showing the data I selected?
Excel may have selected the wrong range or interpreted rows and columns in the wrong direction. Use Select Data to inspect the series and category labels, and try Switch Row/Column if needed. Also verify that the plotted values are numeric.

Try it: the Percentage Formula Generator: percent of, percent change, increase and decrease, with the formula.

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