--- title: "Merge Multiple Excel Files into One in Just 3 Steps Using C#" published_at: "2023-12-01T10:38:42+00:00" modified_at: "2025-11-14T12:42:21+00:00" url: "https://www.syncfusion.com/blogs/post/merge-multiple-excel-csharp" excerpt: "This blog explains how to merge multiple Excel documents into a single file using the Syncfusion Excel Library in C#." taxonomy_category: - "C#" - "Excel" - "File Formats" - "Syncfusion" - "XlsIO" taxonomy_post_tag: - ".NET" - "C#" - "Essential XlsIO" - "File Formats" - "Syncfusion" --- # Merge Multiple Excel Files into One in Just 3 Steps Using C# [Mohan Chandran](https://www.syncfusion.com/blogs/author/mohan-chandran) ![Merge Multiple Excel Files into One in Just 3 Steps Using C#](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Merge-Multiple-Excel-Files-into-One-in-Just-3-Steps-Using-CSharp.png) In today’s data-centric world, dealing with related data spread over various Excel documents can be challenging. The traditional method of manually merging these documents into a unified one can be time-consuming and susceptible to errors. But what if there was a more efficient solution? The [Syncfusion Excel Library](https://www.syncfusion.com/document-sdk/net-excel-library) is a robust tool that facilitates the smooth creation, reading, and editing of Excel documents using C#. This library lets you open and consolidate numerous Excel documents into a single document with just a few lines of code, automating the process, saving valuable time, and ensuring data precision. Whether navigating through many Excel documents, each holding a fragment of a larger whole, or simply seeking a more efficient data management method, this blog is here to assist you. We will guide you through the steps to merge Excel documents using C#, simplifying your data management tasks. Let’s get started! **Note:** If you are new to our Excel Library, following our [Getting Started guide](https://help.syncfusion.com/file-formats/xlsio/getting-started-create-excel-file-csharp-vbnet) is highly recommended. ## How to merge Excel files with C# Follow these steps to merge multiple Excel documents into a single file using the Syncfusion Excel Library in C#: **Step 1:** First, launch [Visual Studio](https://visualstudio.microsoft.com/) . Then, [create a new .NET Core console application](https://learn.microsoft.com/en-us/dotnet/core/tutorials/with-visual-studio?pivots=dotnet-8-0) .![Create a .NET Core Console application](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Create-a-.NET-Core-Console-application.png) **Step 2**: Download and install the most recent version of the [Syncfusion.XlsIO.Net.Core](https://www.nuget.org/packages/Syncfusion.XlsIO.Net.Core) NuGet package.![Install Syncfusion.XlsIO.Net.Core NuGet package](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Install-Syncfusion.XlsIO_.Net_.Core-NuGet-package..png) **Step 3**: Finally, add the following code to the ** Program.cs** file to merge Excel documents from a designated folder path. ``` using Syncfusion.XlsIO; namespace MergeExcel { class Program { static void Main(string[] args) { string inputPath = @"../../../Data/"; string outputPath = @"../../../Output/"; FileInfo[] files = new DirectoryInfo(inputPath).GetFiles(); List streams = new List(); foreach (FileInfo file in files) { streams.Add(file.OpenRead()); } Stream mergedStream = MergeExcelDocuments(streams); FileStream fileStream = new FileStream(outputPath + "MergedExcel.xlsx", FileMode.Create, FileAccess.Write); mergedStream.Position = 0; mergedStream.CopyTo(fileStream); fileStream.Close(); } /// /// Merge Excel documents from the list of Excel streams. /// /// List of Excel document stream to be merged /// public static Stream MergeExcelDocuments(List streams) { using (ExcelEngine excelEngine = new ExcelEngine()) { IApplication application = excelEngine.Excel; application.DefaultVersion = ExcelVersion.Xlsx; IWorkbook workbook = application.Workbooks.Create(0); //Loop through each Excel document and add the worksheets to the new workbook. foreach (Stream stream in streams) { stream.Position = 0; IWorkbook tempWorkbook = application.Workbooks.Open(stream); workbook.Worksheets.AddCopy(tempWorkbook.Worksheets); tempWorkbook.Close(); } //Save the workbook to a memory stream. MemoryStream memoryStream = new MemoryStream(); workbook.Version = ExcelVersion.Xlsx; workbook.SaveAs(memoryStream); return memoryStream; } } } } ``` Refer to the following images showing the input Excel documents. ![Input Excel document](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Input-Excel-document-1.png)![Input Excel document](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Input-Excel-document-2.png)![Input Excel document](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Input-Excel-document-3-1.png) *Input Excel documents* After executing the previous code example, the output will look like the following image. See the number of Excel sheets added at the bottom of the Excel file. ![Merging multiple Excel documents with the Syncfusion Excel Library using csharp](https://www.syncfusion.com/blogs/wp-content/uploads/2023/12/Merging-multiple-Excel-documents-with-the-Syncfusion-Excel-Library-using-csharp.png) Merging multiple Excel documents with the Syncfusion Excel Library using C# ## GitHub reference You can download the example for merging Excel documents in C# on [this GitHub page](https://github.com/SyncfusionExamples/XlsIO-Examples/tree/master/Real%20Time%20Examples%20in%20Excel/Merge%20Excel%20Documents/.NET%20Core) . ## Wrapping up Thanks for reading! As you can see, the [Syncfusion Excel (XlsIO) Library](https://www.syncfusion.com/document-sdk/net-excel-library) lets you effortlessly merge multiple Excel documents into a single document in C# with just three simple steps. Take a moment to peruse the Excel Library [documentation](https://help.syncfusion.com/file-formats/xlsio/working-with-data#importing-data-to-worksheets) , where you’ll find other importing options and features like [data tables](https://help.syncfusion.com/file-formats/xlsio/working-with-data#import-data-from-datatable) , [collection objects](https://help.syncfusion.com/file-formats/xlsio/working-with-data#import-data-from-collection-objects) , [grid view](https://help.syncfusion.com/file-formats/xlsio/working-with-data#import-data-from-dataview) , [data columns](https://help.syncfusion.com/file-formats/xlsio/working-with-data#import-data-from-datacolumn) , and [HTML](https://help.syncfusion.com/file-formats/xlsio/working-with-data#importing-html-table-to-excel-worksheet) , all with accompanying code samples. Using the Excel Library, you can export Excel data to [PDFs](https://help.syncfusion.com/file-formats/xlsio/excel-to-pdf-conversion) , [images](https://help.syncfusion.com/file-formats/xlsio/worksheet-to-image-conversion) , [data tables](https://help.syncfusion.com/file-formats/xlsio/working-with-data#exporting-from-worksheet-to-data-table) , [CSV](https://www.syncfusion.com/kb/9092/convert-excel-file-to-csv-in-c-vb-net) , [TSV](https://www.syncfusion.com/kb/8556/does-xlsio-support-tsv-files) , [HTML](https://help.syncfusion.com/file-formats/xlsio/working-with-excel-worksheet?_ga=2.19528508.561950334.1598519523-255771547.1598519523#save-worksheet-as-html) , [collections of objects](https://help.syncfusion.com/file-formats/xlsio/working-with-data#exporting-from-worksheet-to-clr-objects) , [ODS](https://help.syncfusion.com/file-formats/xlsio/excel-to-ods-conversion) , [JSON](https://help.syncfusion.com/file-formats/xlsio/excel-to-json-conversion) , and other file formats. Are you already a Syncfusion user? You can download the product setup after [logging in](https://www.syncfusion.com/account/downloads/studio/) . If you’re not yet a Syncfusion user, you can download a free 30-day trial [from this page](https://www.syncfusion.com/downloads) . Please let us know in the comments section below if you have any questions about these features. You can also contact us through our [support forum](https://www.syncfusion.com/forums) , [support portal](https://www.syncfusion.com/support/) , or [feedback portal](https://www.syncfusion.com/feedback/excel) . We are always happy to assist you! ## Related blogs - [6 Easy Ways to Export Data to Excel in C#](https://www.syncfusion.com/blogs/post/6-easy-ways-to-export-data-to-excel-in-c-sharp.aspx) - [Seamlessly Import and Export CSV Data in Excel Using C#](https://www.syncfusion.com/blogs/post/import-export-csv-data-in-excel-csharp.aspx) - [How to Export Data from SQL Server to Excel Tables in C#](https://www.syncfusion.com/blogs/post/export-data-from-sql-server-to-excel-in-c-sharp.aspx) - [Export Data from Collections to Excel and Group It in C#](https://www.syncfusion.com/blogs/post/export-data-from-collection-to-excel-and-group-csharp.aspx) - [Export Data to a Predefined Excel Template in C#](https://www.syncfusion.com/blogs/post/export-data-to-a-predefined-excel-template-in-c.aspx) - [Easy Steps to Export HTML Tables to an Excel Worksheet in C#](https://www.syncfusion.com/blogs/post/easy-steps-to-export-html-tables-to-an-excel-worksheet-in-c.aspx)