Working with monthly Excel sheets is a common scenario for analysts. While organizing each month’s data on separate sheets makes it easier to maintain, analyzing trends across all months becomes difficult — unless you consolidate them.
In this blog, I will walk you through how I used Append Queries in Power BI to combine three sheets — Sales in Jan, Sales in Feb, and Sales in Mar — from an Excel workbook titled “Append Tables”, each containing just three columns: Date, Product, and Sales.
You will also learn the key rules to follow while appending tables, so your combined data stays clean and accurate.

What is Append Queries?

Append Queries is a transformation in Power BI that allows you to combine rows from two or more tables
with the same structure. Think of it as stacking data vertically, one table below the other — just like
combining three monthly sales reports into one master list.

What I Did: Steps to Append the Monthly Sheets

Here's how I appended the three monthly sheets in Power BI:
1. Imported the Excel File: Loaded the “Append Tables” workbook into Power BI.
2. Loaded the Sheets Individually: Selected and loaded Sales in Jan, Sales in Feb, and Sales in Mar as separate queries.
3. Opened Power Query Editor: Clicked on Transform Data to access the Power Query Editor.
4. Appended the Queries:
o Used Append Queries as New.
o Selected the option to append three or more tables.
o Added the three monthly sheets.
o Renamed the new query to All Sales Data.

After these steps, I had a single table containing all sales transactions across the three months — ready for analysis and visualization.

Important Rules to Remember When Appending Tables

To ensure your append operation works smoothly, follow these three essential rules:
1. Same Number of Columns
Each sheet must have the same number of columns. In this case, all three sheets had exactly three: Date, Product, and Sales.
2. Column Names Must Match
Power BI matches data based on column names, not just positions. If any column name is spelled differently
(e.g., Product vs. product), the append will produce unexpected results.
3. Data Types Should Be Consistent
Make sure that the data types of each column are identical across all sheets. For example:
• Date should be in Date format
• Product should be Text
• Sales should be a Numeric type
This ensures proper alignment and avoids data conversion issues.

Why Use Append Queries?

Using Append Queries is ideal when:
• You receive recurring data (e.g., monthly reports) in the same structure.
• You want to analyze trends over time in a single Power BI dashboard.
• You need to automate data processing instead of manually copying and pasting.

Appending multiple monthly sheets into one table is a fundamental and highly useful skill in Power BI. It simplifies your data model, makes trend analysis easier, and saves time by automating repetitive tasks.