Following on from a previous question I am creating a document which inserts a number of appendices each one numbered with the Seq command as follows

appendix Seq



The number of Appendices may change

I would like to list each Appendix heading in the document..is that possible

You may want to look at How to number headings and figures in Appendixes in Microsoft Word by Shauna Kelly.
You can do this with a Table of Contents, or a cross-reference if you use the method given by Shauna.
This does not involve using the SEQ field. For that you would need to take extra steps to bookmark each Appendix Heading.

There are good reasons to make use of the article for which Charles provided a link (How to number headings and figures in Appendixes in Microsoft Word | ShaunaKelly.com).

On the other hand, if you prefer not to apply numbering to headings and just use SEQ fields, that is going to work too. You will have to create two sequences, one for the main chapters and a separate sequence for the appendix. If you want multilevel numbering, SEQ fields will be a far more difficult approach, though.

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Stefan Blom
Microsoft Word MVP

Microsoft 365 apps for business
Windows 11 Professional