Make a heading style appear in the table of contents

Make the appendix headings use a style and outline level that the table of contents (TOC) is set up to include.

1. Apply a heading style that the TOC already uses
   • Select an appendix heading (for example, “Appendix I.”).
   • On the Home tab, in Styles, apply Heading 1, Heading 2, or Heading 3 (whichever level is appropriate for the TOC).
   • Update the TOC: right‑click the table of contents and choose Update Field.
   • If the appendix headings now appear, repeat for all appendix headings.
2. Or, add the appendix style as a TOC style (custom TOC) If the appendices use a custom style (for example, a style named “Appendix”), add that style to the TOC definition:
   1. Click anywhere in the existing TOC.
   2. Go to References > Table of Contents > Custom Table of Contents.
   3. Choose Options (from the Custom TOC dialog) and map the “Appendix” style to a TOC level (for example, level 1 or 2). Confirm and select OK.
   4. Update the TOC.
3. Ensure the style name is correct If a custom style is used, verify the style name is spelled exactly the same everywhere. A misspelled or slightly different style name will not be picked up by the TOC.
4. Use heading styles for easiest TOC generation Built‑in heading styles (Heading 1–Heading 3 by default) are the most reliable way to ensure headings, including appendices, appear in the TOC. Apply these styles to any text that should be included.

References:

• Insert a table of contents
• Format or customize a table of contents in Word
• The Styles advantage in Word
• HeadingStyles object (Word)
• TablesOfContents.Add method (Word)
• How can I add or code text items to show in the Table of Contents? - Microsoft Q&A
• How to EDIT an existing table of contents, NOT update it or create a new one - Microsoft Q&A