You have two versions of the same document with tracked changes from different reviewers. You need to combine them into one document so you can see all edits in a single view. Word provides a built-in Compare and Combine feature that merges tracked changes from multiple copies into one final document. This article explains how to use the Combine command, what prerequisites are needed, and what to do when the merge does not behave as expected.
Key Takeaways: Merging Two Word Documents With Tracked Changes
- Review > Compare > Combine: The exact command that merges tracked changes from two documents into a single file.
- Original document and Revised document: Both files must share the same base text for a clean merge; otherwise, Word highlights mismatches as unresolved conflicts.
- Combine shows changes from both authors in one document: Each reviewer’s edits appear in a different color with their name in the markup balloons.
How the Combine Feature Works in Word
The Combine command is part of Word’s Compare group on the Review tab. It is designed specifically for merging tracked changes from two versions of the same document. The feature compares the original document with a revised copy and then creates a new document that contains all tracked changes from both files. Word labels each change with the original author’s name or the reviser’s name, depending on which version the change came from.
Before you start, you must have both files saved on your computer or network drive. The documents should be based on the same original text. If the two files have different starting content, Word will still attempt a merge, but the result may contain unresolved conflicts that appear as strikethrough and underline markup. The Combine feature works in Word 2013, Word 2016, Word 2019, Word 2021, and Word for Microsoft 365.
What the Combine Command Does Not Do
The Combine command is not the same as the Compare command. Compare shows the differences between two documents but does not merge them into one editable file with both sets of tracked changes. Combine creates a new document that contains all changes from both sources. It also does not merge comments. Comments from the revised document are carried over, but comments from the original document are not included in the merged output.
Steps to Merge Two Word Documents With Tracked Changes
Follow these steps to combine two documents into one file that shows tracked changes from both reviewers.
- Open the original document
Open the document that represents the starting version before any edits were made. This file is labeled as the Original document in the Combine dialog. You can open either of the two files; Word will ask you to select both. - Go to Review > Compare > Combine
Click the Review tab on the ribbon. In the Compare group, click the Compare button and then select Combine from the dropdown menu. The Combine Documents dialog box opens. - Select the Original document
In the Original document dropdown, choose the file that contains the base text before any tracked changes were made. If the file is not listed, click the Browse button and locate it on your computer. - Select the Revised document
In the Revised document dropdown, choose the file that contains the tracked changes you want to merge. This is the document that was edited by a reviewer. Click Browse if needed. - Label changes from the revised document
In the Label changes with box, type a name that identifies the reviewer of the revised document. This name appears in the markup balloons and in the Reviewing Pane. The original document’s author name is preserved automatically. - Set the comparison options
Click the More button to expand the dialog. Check or uncheck the comparison settings as needed. The default options are usually sufficient. The key settings are:
– Insertions and deletions: Always checked.
– Moves: Tracks when text is moved from one location to another.
– Formatting: Tracks font, size, and style changes.
– Show changes at: Select Character level for the most detailed comparison, or Word level to reduce noise. - Choose where to show changes
In the Show changes in section, select New document. This creates a fresh file that contains the merged result. The other options (Original document and Revised document) apply changes directly to one of the existing files, which can overwrite your original work. - Click OK to run the merge
Word processes the two documents and opens a new document with the combined tracked changes. Reviewing Pane appears on the left side, showing a summary of all changes. The main document displays the merged text with markup balloons and tracked change marks. - Save the merged document
Press Ctrl+S or go to File > Save As. Give the file a new name so you do not overwrite either of the source documents.
If You Need to Merge More Than Two Documents
The Combine command merges only two documents at a time. To merge three or more versions, run the Combine command repeatedly. Start with the original document and the first revised copy. Then use the result as the Original document and combine it with the next revised copy. Repeat until all versions are merged.
Common Merge Problems and How to Resolve Them
“The documents cannot be combined because they are based on different originals”
This error occurs when the two documents have different starting text. Word compares the files to find a common base. If the base text is too different, the merge fails. To fix this, ensure both documents were created from the same original file. If one reviewer accidentally started from a different version, ask that reviewer to copy their changes into the correct base document manually.
Merged document shows duplicate content or missing text
Word may misinterpret heavily edited sections, especially when both reviewers changed the same paragraph. Open the Reviewing Pane by clicking Review > Reviewing Pane. Check each change and accept or reject it. Look for unresolved conflicts marked with strikethrough and underline in the same location. Accept the correct version and reject the duplicate.
Author names appear as “Unknown” or generic labels
The author name comes from the user information stored in each document. To fix this, open the revised document, go to File > Info, and check the Author property. If it is blank, add the correct name. Then run the Combine command again. You can also set the label manually in the Combine dialog before clicking OK.
Comments are missing in the merged document
Comments from the revised document are included in the merge. Comments from the original document are not carried over. If you need comments from both files, copy them manually after the merge. Open the original document, select a comment, copy it, and paste it into the merged document at the corresponding location.
Combine vs Compare: Key Differences
| Item | Combine | Compare |
|---|---|---|
| Output | New document with tracked changes from both files | New document showing differences only, no tracked changes |
| Editable tracked changes | Yes, both sets of changes appear as tracked changes | No, differences appear as markup but are not tracked changes |
| Comments included | Only from the revised document | From both documents |
| Best use case | Merging edits from multiple reviewers on the same base document | Comparing two versions to see what changed without merging |
Use Combine when you need to preserve tracked changes from each reviewer in a single document. Use Compare when you only need a list of differences and do not need to accept or reject edits later.
You can now merge two Word documents with tracked changes using the Review > Compare > Combine command. After the merge, open the Reviewing Pane to inspect all changes and accept or reject them as needed. For complex multi-reviewer workflows, repeat the Combine command sequentially. As an advanced tip, use the Show Markup > Specific People option to filter changes by reviewer so you can review each author’s edits separately before finalizing the document.