foot the bill
Pay the bill, settle the accounts, as in The bride's father was resigned to footing the bill for the wedding. This expression uses foot in the sense of “add up and put the total at the foot, or bottom, of an account.” [Colloquial; early 1800s]
The American Heritage® Idioms Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.