"Also look for pesky rows that span all the columns in your table, that may be hiding at the bottom of the page. When you delete them the extra page will go away."
Thanks for the tip, Leeand00. I had an extra blank page showing up in Print Preview and printing after an invoice form I'd developed in Calc. After fiddling with a bunch of things, I discovered it was a column spanning cell near the bottom of the page. It wasn't even all columns, just about 70% of them. When I reduced how many columns it spanned, (resplit the cells then remerged) the extra page vanished.
The ones higher on the page didn't matter, just the one in the last inch.