"What’s the damage?” means “What’s the cost (of the meal)?” The question is often said to a waiter, who then presents the bill. The phrase is also said by a diner to the person at the restaurant table reading the bill.
‘What’s the damage?” is cited in print from the 1700s. The dining usage of ‘What’s the damage?” dates to at least 1801.
“The bad news” is another expression for the check.
The Free Dictionary
What’s the damage?
Sl. What are the charges?; How much is the bill? Bill: That was delicious. Waiter, what’s the damage? Waiter: I’ll get the check, sir. Waiter: Your check sir. Tom: Thanks. Bill: What’s the damage, Tom? Let me pay my share. Tom: Nonsense, I’ll get it. Bill: Okay this time, but I owe you one.
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs. © 2002
What’s the damage? (informal, humorous)
used to ask how much you have to pay for something ‘We’ve mended your car.’ ‘Great. What’s the damage?’
Cambridge Idioms Dictionary, 2nd ed. Copyright © Cambridge University Press 2006.
(Oxford English Dictionary)
slang. Cost, expense. Esp. in phr. what’s the damage? how much is there to pay?
1755 Connoisseur No. 68 10 ‘There’, says he, ‘there’s your damage—thirteen and two-pence.’
1812 BYRON Wks. (1832) II. 179, I must pay the damage, and will thank you to tell me the amount of the engraving.
1829 J. HUNTER Hallamshire Gloss. 29 ‘What is the damage?’ This expression is equivalent to ‘What expence have I incurred?’ ‘What must I pay?’
1852 MRS. STOWE Uncle Tom’s C. xiv, What’s the damage, as they say in Kentucky..what’s to be paid out for this business?
Farther excursions of the observant pedestrian, exemplified in a tour to Margate
London, R. Dutton
The waiter entered with obsequious cringe.
“Bring the bill—let’s know what’s the damage, and order my servants to draw up the tandems.”
3 September 1835, Army and Navy Chronicle, pg. 281, col. 2:
“What’s the damage?” exclaimed he, as the boat came alongside.
“Sir?” said the boatman.
“Why, what’s to pay?”
24 January 1846, The Sportsman’s Magazine of life in London and the country, pg. 543, col. 2:
“Now, then, yong imp, what’s the damage”
“Sixpence, please sir,” said the waiter, ...
Life and adventures of Valentine Vox, the ventriloquist
By Henry Cockton
New York, NY: F. Warne
“Waitor! now then, what’s the damage?”
“‘Am an’ beef, sir, cheese, sir, bread, bottle stout—seven an’ six.”
Mr. Potter of Texas : a novel
By Archibald Clavering Gunter
New York, NY: Home Pub. Co.
...Mr. Potter rises, looks out of the window, and says, suddenly: “What’s the damage?”
“Damage?” echoes Lubbins, not understanding this Americanism.
“Yes; how much do I owe?”
Thus adjured, the waiter bolts for the bill, while Potter, sitting down to wait for him, gazes abstractedly at the Times that still lies on the table before him.
Slang and its analogues past and present. A dictionary ... with synonyms in English, French ... etc.
Compiled by J.S. Farmer and W.E. Henley
London: Harrison & Sons
DAMAGE, subv. (colloquial).—The cost of anything; the sum total in the sense of recompense. “What’s the DAMAGE?”