"Repeat header row" is set, but not repeating

Word repeats headers only when the selected rows are the table’s leading rows and the table flows continuously across pages. Select the entire first row, not just its text, then open Table Properties > Row and confirm Repeat as header row at the top of each page. Switch to Print Layout and check Print Preview, because repeated headers are not displayed in every view. Turn on formatting marks and verify there is no manual page break, paragraph, or second table between the first-page portion and its continuation. In Table Properties > Table, temporarily set Text wrapping to None; a floating table can behave differently from an inline table. Confirm the apparent header is not built with merged cells extending into non-header rows. “Allow row to break across pages” controls row splitting and does not enable header repetition.