How to Add Comment in Excel with C# (without Interop)

Add comments to Excel cells in C# using IronXL's simple API—no interop required. Just call AddComment() on any cell to add notes, annotations, or explanations that won't affect your cell data.

Quickstart: Add a Comment to a Cell in One Simple Line

Add a comment to any Excel cell with a single method call. No interop, no complexity—just call AddComment on a cell and you're done.

```cs:title=Add an Excel Comment in One Line with IronXL IronXL.WorkBook.Create().DefaultWorkSheet["B2"].First().AddComment("Quick tip!", "Dev");

<div class="hsg-featured-snippet">
    <h3>Minimal Workflow (5 steps)</h3>
    <ol>
        <li><a class="js-modal-open" data-modal-id="trial-license-after-download" href="https://nuget.org/packages/IronXL.Excel/">Download the C# library to enable comment functionality</a></li>
        <li>Open an existing or create a new Excel spreadsheet</li>
        <li>Use the <code>AddComment</code> method to add comments</li>
        <li>Retrieve and edit comments by accessing the <strong>Comment</strong> property</li>
        <li>Remove comments from cells using the <code>RemoveComment</code> method</li>
    </ol>
</div>
<br class="clear">

## How Do I Add Comments to Excel Cells?

### What Parameters Does AddComment Accept?

Select the cell and use the `AddComment` method to add a comment to the cell. By default, the comment will be invisible. Hover over the cell to see the comment. The AddComment method accepts three parameters: content (string), author (string), and isVisible (boolean). Both content and author parameters are optional and can be null, allowing you to create empty comments or comments without author attribution.

When working with Excel comments in your .NET applications, understanding how IronXL handles cell referencing is essential. If you're new to IronXL, check out the comprehensive [getting started overview](https://ironsoftware.com/csharp/excel/docs/) to understand the basics of working with Excel files programmatically. For enterprise applications requiring cloud deployment, IronXL seamlessly integrates with [Azure environments](https://ironsoftware.com/csharp/excel/get-started/azure/) and [AWS Lambda functions](https://ironsoftware.com/csharp/excel/get-started/aws/).

### When Should I Make Comments Visible by Default?

Comments are typically hidden by default in Excel to maintain a clean spreadsheet appearance. However, you might want visible comments in scenarios like creating training materials, providing detailed instructions for data entry, or highlighting critical information that users must see immediately. Set the third parameter of AddComment to true to make comments visible without hovering.

For more advanced Excel manipulation tasks, including [creating new spreadsheets](https://ironsoftware.com/csharp/excel/how-to/create-spreadsheet/) from scratch or [managing existing worksheets](https://ironsoftware.com/csharp/excel/how-to/manage-worksheet/), IronXL provides a comprehensive set of tools that work seamlessly together. When building data-driven applications, you might also need to [export Excel data to various formats](https://ironsoftware.com/csharp/excel/how-to/c-sharp-export-to-excel/) or [convert between different spreadsheet types](https://ironsoftware.com/csharp/excel/how-to/convert-spreadsheet-file-types/).

### What Happens If I Add a Comment to a Cell That Already Has One?

When you call AddComment on a cell that already contains a comment, IronXL will replace the existing comment with the new one. This behavior ensures you don't accidentally create duplicate comments on a single cell. If you need to preserve existing comment content, first retrieve it using the Comment property, then concatenate or merge the content before adding the updated comment.

```csharp
:path=/static-assets/excel/content-code-examples/how-to/add-comment-add-comment.cs

Here's a practical example of adding comments to multiple cells in a loop, useful for adding batch annotations or validation notes:

using IronXL;
using System;

// Load an existing workbook
WorkBook workBook = WorkBook.Load("salesData.xlsx");
WorkSheet workSheet = workBook.DefaultWorkSheet;

// Add comments to cells that meet specific criteria
for (int row = 2; row <= 10; row++)
{
    var cell = workSheet[$"D{row}"].First();
    var value = cell.DoubleValue;

    if (value > 1000)
    {
        // Add performance comment for high values
        cell.AddComment($"Excellent performance! Value: {value:C}", "Sales Manager", true);
    }
    else if (value < 500)
    {
        // Add improvement comment for low values
        cell.AddComment($"Needs attention. Current: {value:C}", "Sales Manager", false);
    }
}

// Add timestamp comment to track last update
var updateCell = workSheet["A1"].First();
updateCell.AddComment($"Last updated: {DateTime.Now:yyyy-MM-dd HH:mm}", "System");

workBook.SaveAs("salesDataWithComments.xlsx");

using IronXL;
using System;

// Load an existing workbook
WorkBook workBook = WorkBook.Load("salesData.xlsx");
WorkSheet workSheet = workBook.DefaultWorkSheet;

// Add comments to cells that meet specific criteria
for (int row = 2; row <= 10; row++)
{
    var cell = workSheet[$"D{row}"].First();
    var value = cell.DoubleValue;

    if (value > 1000)
    {
        // Add performance comment for high values
        cell.AddComment($"Excellent performance! Value: {value:C}", "Sales Manager", true);
    }
    else if (value < 500)
    {
        // Add improvement comment for low values
        cell.AddComment($"Needs attention. Current: {value:C}", "Sales Manager", false);
    }
}

// Add timestamp comment to track last update
var updateCell = workSheet["A1"].First();
updateCell.AddComment($"Last updated: {DateTime.Now:yyyy-MM-dd HH:mm}", "System");

workBook.SaveAs("salesDataWithComments.xlsx");

IRON VB CONVERTER ERROR developers@ironsoftware.com

:path=/static-assets/excel/content-code-examples/how-to/add-comment-edit-comment.cs

using IronXL;
using System.Linq;

WorkBook workBook = WorkBook.Load("addComment.xlsx");
WorkSheet workSheet = workBook.DefaultWorkSheet;

Cell cellA1 = workSheet["A1"].First();

// Retrieve comment
var comment = cellA1.Comment;

// Edit comment
comment.Author = "Jane Doe";
comment.Content = "Bye World";
comment.IsVisible = true;

workBook.SaveAs("editComment.xlsx");

Imports IronXL
Imports System.Linq

Private workBook As WorkBook = WorkBook.Load("addComment.xlsx")
Private workSheet As WorkSheet = workBook.DefaultWorkSheet

Private cellA1 As Cell = workSheet("A1").First()

' Retrieve comment
Private comment = cellA1.Comment

' Edit comment
comment.Author = "Jane Doe"
comment.Content = "Bye World"
comment.IsVisible = True

workBook.SaveAs("editComment.xlsx")

:path=/static-assets/excel/content-code-examples/how-to/add-comment-remove-comment.cs

using IronXL;
using System.Linq;

WorkBook workBook = WorkBook.Load("addComment.xlsx");
WorkSheet workSheet = workBook.DefaultWorkSheet;

Cell cellA1 = workSheet["A1"].First();

// Remove comment
cellA1.RemoveComment();

workBook.SaveAs("removeComment.xlsx");

Imports IronXL
Imports System.Linq

Private workBook As WorkBook = WorkBook.Load("addComment.xlsx")
Private workSheet As WorkSheet = workBook.DefaultWorkSheet

Private cellA1 As Cell = workSheet("A1").First()

' Remove comment
cellA1.RemoveComment()

workBook.SaveAs("removeComment.xlsx")