diff --git a/src/Umbraco.Core/Models/ValueStorageType.cs b/src/Umbraco.Core/Models/ValueStorageType.cs
index 975369f993..e7e4f8b354 100644
--- a/src/Umbraco.Core/Models/ValueStorageType.cs
+++ b/src/Umbraco.Core/Models/ValueStorageType.cs
@@ -14,13 +14,13 @@ public enum ValueStorageType
     // changing the casing of values.
 
     /// <summary>
-    ///     Store property value as NText.
+    ///     Store property value as NVarchar(max).
     /// </summary>
     [EnumMember]
     Ntext,
 
     /// <summary>
-    ///     Store property value as NVarChar.
+    ///     Store property value as NVarChar(512).
     /// </summary>
     [EnumMember]
     Nvarchar,
diff --git a/src/Umbraco.Core/PropertyEditors/ValueTypes.cs b/src/Umbraco.Core/PropertyEditors/ValueTypes.cs
index ac6e6a9bb8..dc1e636c7f 100644
--- a/src/Umbraco.Core/PropertyEditors/ValueTypes.cs
+++ b/src/Umbraco.Core/PropertyEditors/ValueTypes.cs
@@ -45,7 +45,7 @@ public static class ValueTypes
     public const string Json = "JSON"; // NText
 
     /// <summary>
-    ///     Text value (maps to text database type).
+    ///     Text value (maps to nvarchar(max) database type).
     /// </summary>
     public const string Text = "TEXT"; // NText
 
@@ -55,7 +55,7 @@ public static class ValueTypes
     public const string Time = "TIME"; // Date
 
     /// <summary>
-    ///     Text value (maps to varchar database type).
+    ///     Text value (maps to nvarchar(512) database type).
     /// </summary>
     public const string String = "STRING"; // NVarchar
 
diff --git a/src/Umbraco.Infrastructure/Migrations/Install/DatabaseDataCreator.cs b/src/Umbraco.Infrastructure/Migrations/Install/DatabaseDataCreator.cs
index e99ce46587..7fed5a6afb 100644
--- a/src/Umbraco.Infrastructure/Migrations/Install/DatabaseDataCreator.cs
+++ b/src/Umbraco.Infrastructure/Migrations/Install/DatabaseDataCreator.cs
@@ -2060,7 +2060,7 @@ internal sealed class DatabaseDataCreator
                     NodeId = -43,
                     EditorAlias = Constants.PropertyEditors.Aliases.CheckBoxList,
                     EditorUiAlias = "Umb.PropertyEditorUi.CheckBoxList",
-                    DbType = "Nvarchar",
+                    DbType = "Ntext",
                 });
         }
 
diff --git a/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs b/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
index b02c56fea6..a62ce1d8a1 100644
--- a/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
+++ b/src/Umbraco.Infrastructure/Migrations/Upgrade/UmbracoPlan.cs
@@ -126,5 +126,6 @@ public class UmbracoPlan : MigrationPlan
 
         // To 17.0.0
         To<V_17_0_0.AddGuidsToAuditEntries>("{17D5F6CA-CEB8-462A-AF86-4B9C3BF91CF1}");
+        To<V_17_0_0.MigrateCheckboxListDataTypesAndPropertyData>("{EB1E50B7-CD5E-4B6B-B307-36237DD2C506}");
     }
 }
diff --git a/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_0_0/MigrateCheckboxListDataTypesAndPropertyData.cs b/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_0_0/MigrateCheckboxListDataTypesAndPropertyData.cs
new file mode 100644
index 0000000000..35873b9501
--- /dev/null
+++ b/src/Umbraco.Infrastructure/Migrations/Upgrade/V_17_0_0/MigrateCheckboxListDataTypesAndPropertyData.cs
@@ -0,0 +1,50 @@
+using Umbraco.Cms.Core;
+using Umbraco.Cms.Core.Models;
+using Umbraco.Cms.Core.Services;
+
+namespace Umbraco.Cms.Infrastructure.Migrations.Upgrade.V_17_0_0;
+
+/// <summary>
+/// Migrates data types based on the Umbraco.CheckBoxList property editor to store data in the text column without length restriction.
+/// Also migrates the data for properties this property editor from the length restricted field (varcharValue - nvarchar(512)), to the
+/// one without a restriction (textValue - nvarchar(max)).
+/// </summary>
+public class MigrateCheckboxListDataTypesAndPropertyData : AsyncMigrationBase
+{
+    private readonly IDataTypeService _dataTypeService;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="MigrateCheckboxListDataTypesAndPropertyData"/> class.
+    /// </summary>
+    public MigrateCheckboxListDataTypesAndPropertyData(IMigrationContext context, IDataTypeService dataTypeService)
+        : base(context) => _dataTypeService = dataTypeService;
+
+    /// <inheritdoc/>
+    protected override async Task MigrateAsync()
+    {
+        // Update the definition of the datatypes.
+        IEnumerable<IDataType> dataTypes = await _dataTypeService.GetByEditorAliasAsync(Constants.PropertyEditors.Aliases.CheckBoxList);
+        foreach (IDataType dataType in dataTypes)
+        {
+            dataType.DatabaseType = ValueStorageType.Ntext;
+            await _dataTypeService.UpdateAsync(dataType, Constants.Security.SuperUserKey);
+        }
+
+        // Copy from varcharValue to textValue and set varcharValue to null for all property data stored using data types based on
+        // the Umbraco.CheckBoxList property editor.
+        string sql = $@"
+UPDATE umbracoPropertyData
+SET textValue = varcharValue, varcharValue = NULL
+WHERE propertyTypeId IN (
+	SELECT id
+    FROM cmsPropertyType
+	WHERE dataTypeId IN (
+		SELECT nodeId
+        FROM umbracoDataType
+        WHERE propertyEditorAlias = '{Constants.PropertyEditors.Aliases.CheckBoxList}'
+	)
+)
+AND varcharValue IS NOT NULL";
+        await Database.ExecuteAsync(sql);
+    }
+}
diff --git a/src/Umbraco.Infrastructure/PropertyEditors/CheckBoxListPropertyEditor.cs b/src/Umbraco.Infrastructure/PropertyEditors/CheckBoxListPropertyEditor.cs
index cd06118041..9f9606e3f0 100644
--- a/src/Umbraco.Infrastructure/PropertyEditors/CheckBoxListPropertyEditor.cs
+++ b/src/Umbraco.Infrastructure/PropertyEditors/CheckBoxListPropertyEditor.cs
@@ -12,6 +12,7 @@ namespace Umbraco.Cms.Core.PropertyEditors;
 /// </summary>
 [DataEditor(
     Constants.PropertyEditors.Aliases.CheckBoxList,
+    ValueType = ValueTypes.Text, // We use the Text value type to ensure we don't run out of storage space in the database field with large lists with multiple values selected.
     ValueEditorIsReusable = true)]
 public class CheckBoxListPropertyEditor : DataEditor
 {