The phrase a penny bun costs twopence, or tuppence, means that expenses rise as soon as one marries or begins cohabiting, or even carries on a romantic relationship.
Death from Starvation.—Yesterday morning about 10 o’clock, a poor man named George ——, apparently about 36 years of age, who was usually employed in carrying fish for the women who sell it on the Coal-Quay, while passing through Patrick-street with a basket of fish on his head, fell at the end of Carey’s-lane in a fit. Some persons passing immediately raised him and means were used to recover him, but although Mr. Lucas, Apothecary, and Dr. Kehoe, humanely exerted themselves it was ineffectual, and after struggling for some time he expired. It was said by some of the persons present that they had heard him on that morning say he had eaten during the last two days but one penny bun! He was, indeed, a miserable looking object.
The phrase a penny bun costs twopence is opposite in meaning to two can live as cheaply as one—as illustrated by the beginning of Pop goes the money, by Douglas Warth, published in the Daily Herald (London, England) of Friday 22nd March 1957:
Love may be a DREAM—but getting married, these days, is a NIGHTMARE.
That is what I learned from scores of newly-weds and young couples on the brink of marriage. I pity anybody who is getting married without a minimum of £400 in the bank and an income of at least £15 a week.
But just you try telling this to half of the 100,000 headstrong boys and girls who are, now, planning a spring wedding.
Point out that, at the best of times, “a penny bun costs tuppence” once you are married—and the kids will snap back at you that “two can live as cheaply as one in a furnished room.”
The earliest occurrence of a penny bun costs twopence that I have found is from The Bitter Bit, a short story by one Radcliffe Martin, published in The Los Angeles Times (Los Angeles, California) of Saturday 12th August 1911—this short story is set at Blackpool, Lancashire, England:
The three walked Blackpool pier as if they owned the earth and Halley’s comet.
“Nothing like a bit of swank,” chuckled Trevor, the oldest. “Look at the girls watching us. Take us for blooming millionaires, you bet.”
“Jolly nice lot of girls about today,” remarked Chaddock. “Pity we can’t pick up with three.”
“Get out—we don’t want to worry with girls,” said the economical Hinks. “If you’ve a girl with you a penny bun costs tuppence, and they’re beasts to make you spend money.”
The second-earliest occurrence of a penny bun costs twopence that I have found is from Chesterfield Races: An Impression, an unsigned article published in The Derbyshire Courier (Chesterfield, Derbyshire, England) of Saturday 31st July 1920—the author punned on a horse’s name and specified that the phrase had already been in use for several years:
Races are an excuse for drinks, cigars, roundabouts, and the exercise of faith, chiefly a pathetic faith that something can be got for nothing.
Most of the hackers [misprint for ‘backers’] were disappointed. They had faith in Lightning, but he belied his name. They had faith in Penny Bun but he failed to rise to the occasion. I mistrusted him myself. His name dated him. A penny bun has cost twopence for years. Obviously a pre-war horse.
The phrase occurs in the portrait of an Egyptian servant named Mahomet, by ‘Muriel’, published in The Courier (Dundee, Angus, Scotland) of Friday 9th December 1921:
Of all the blessings large and small that have been bestowed upon me since I took up my abode in the land of the Pharaohs, Mahomet romps home an easy winner every time.
If it is possible for anyone residing in Britain to imagine one person who counts among his ordinary duties the role of cook, housemaid, valet, charlady, general buyer-in, and umpteen other things besides, then you’ve got some slight idea of the Crichton-like qualities of the Admirable Mahomet. And all this from a mere man.
Mahomet has a wife whom he bought, as is the custom here, for ten pounds—so to celebrate the occasion I gave him a good “rise.” A penny bun costs tuppence here just the same as it does at “home.”
The phrase is elaborated upon in The Penalties of Riches, published in The Yorkshire Post (Leeds, Yorkshire, England) of Wednesday 18th May 1927—Solomon ‘Solly’ Joel (1865-1931) was an English financier:
Mr. Solly Joel, who appears to have that special aptitude for getting himself into the news which is envied by theatrical stars, certain politicians, and some journalists, is to be congratulated on the courage which prompted him to bring into court a tradesman who, he avered [sic], had overcharged him for certain commodities. During the hearing of the case, which ended in a verdict for Mr. Joel, there were revealed in cross-examination some of the penalties which men incur by becoming rich or famous. A learned counsel remarked that the bestowal of knighthood means the creation for the recipient’s benefit of a specially high hotel tariff, and it was also observed that in the presence of a notoriously rich man the merchants depart from that strict standard of charge by market worth which usually prevails, and adopt a standard of prices based on assumed capacity to pay. An ancient cynic held that the chief noticeable effect of matrimony was that after the ceremony a penny bun cost twopence, and that the price increased in ratio to the growth of the family, but the Benedict is fortunate in comparison with the poor millionaire, for whom the price of a penny bun jumps to sixpence or a shilling. A travelling Hanoverian Archduke being charged an excessive price for fresh laid eggs expressed astonishment that they should be so scarce in a country district. “It is not eggs that are scarce; it is Archdukes,” replied the frank inn-keeper. Mr. Joel has suffered from a paucity of plutocrats rather than from any ordinary rapacity in the supplier of his oats.
Winifred Stephenson used the phrase in Should Married Women Work?, published in The Clarion: An Independent Monthly Socialist Review (London, England) of August 1929:
There are girls who get married in a moment of enthusiasm and then find that after the honeymoon a penny bun costs tuppence and ends won’t meet—not, that is, with an adequate allowance for silken raiment and new shoes, and cinemas and extravagant ready-cooked meals.