origin of the Hallowe’en phrase ‘trick or treat’

The phrase trick or treat is a traditional formula used at Hallowe’en by children who call on houses threatening to play a trick unless given a treat or present.

It seems to have originated in Alberta, a province in western Canada.

The earliest instance that I have found is from The Calgary Daily Herald (Calgary, Alberta) of Thursday 3rd November 1927—High River is a town in Alberta:

(Special Dispatch to The Herald)

HIGH RIVER, Nov. 3.—[…]
Hallowe’en came and went and was observed most circumspectly in town, without the usual depredations. The greatest activity was manifested by the very young, who wandered in droves from door to door, heavily disguised and demanding “trick or treat.” To treat was to be untricked, and the youthful hold-up men soon returned home bowed down with treats.

'trick or treat' - Calgary Daily Herald (Calgary, Alberta) - 3 November 1927

The second-earliest occurrence is from The Lethbridge Herald (Lethbridge, Alberta) of Friday 4th November 1927—Blackie is a hamlet in Alberta:

(From Our Own Correspondent.)

BLACKIE, Nov. 3—Hallowe’en provided an opportunity for real strenuous fun. No real damage was done except to the temper of some who had to hunt for wagon wheels, gates, wagons, barrels, etc., much of which decorated the front street. The youthful tormentors were at back door and front demanding edible plunder by the word “trick or treat” to which the inmates gladly responded and sent the robbers away rejoicing.

On Saturday 3rd December 1927, The Morning Leader (Regina, Saskatchewan) published a letter by an 11-year-old girl named Margaret C. Craig, living in the village of Wilcox, Saskatchewan; this letter provides some insight into Hallowe’en celebrations at that time, particularly into the custom of trick or treat (although the little girl does not use the phrase)—Saskatchewan is a province of central Canada:

Here I am again for a little chat to tell you about the Hallowe’en party we had. Well, we had one at the school. We played around for a while till more came then we started our games. Most of us came in costume. I was dressed up as a witch. I surely looked funny. After a while we had a parade to see who looked the funniest. After that we had some games. Then we had a ghost walk. It sure was spooky. There were ghosts all over the school and we followed a teacher around and every few minutes she would turn on a flashlight and we saw the ghosts. We went all through the school. Then we went back to where we played our games and listened to ghost stories. Then we had lunch and went home. I was out on Hallowe’en night and had fun. We had four in our gang when we started and when we ended we had over twenty. I got a lot of treats. At one store we went to there was a sign on the store which said “ice cream.” We got it and ran down the road with it. And the storekeeper came out and chased us away and took the sign back. We couldn’t find another way to bother him so we played some more tricks on other people. I sure had a great time.

In January 1982, The Illustrated London News (London, England) evoked a British custom resembling trick or treat:

The first Monday after Twelfth Night is Plough Monday, when ploughs were blessed to ensure the year’s successful crops. Long ago teams of men would drag a plough through their village to raise money for beery revelry and if denied alms would threaten to plough up the householder’s front path or doorstep. This early trick-or-treat has died out now, but church services are still held in some parishes to bless the plough and on the following Saturday villagers still dance through the streets in Goathland, North Yorkshire.

A description of Hallowe’en festivities in Los Angeles appeared in The Essex Newsman Herald (Chelmsford, Essex, England) of Tuesday 8th November 1949:

Pamela Henderson, formerly of Southend [in Essex], who hopes to break into the film world, writes from Hollywood.

We are about to embark on our first experience of the American conception of Hallowe’en and its amusing superstitions.
For weeks past the stores and shops have sported a varied and colourful selection of masks, table decorations, witches on broomsticks, orange pumpkin, and black cat lampshades, candies, and cakes, designed in keeping with the ancient traditions of Oct. 31st.
Over here they go in for it in a big way by making an early start with a continual stream of youngsters, who make a house-to-house call for their annual gifts of candy, cookies, and fruit, as their share of what is termed the “Trick or Treat” date.
Should the occupiers by any unlucky chance neglect to prepare for this lively event, they are in danger of having a prank played upon them—hence “Trick or Treat.”
However, since it is an acknowledged fact that the good folk on this side are instinctively warm-hearted and hospitable, even more so where children are concerned, they can be relied upon to carry out their part as Hallowe’en hosts and hostesses generously.
Numerous bonfire entertainments for juniors are organised by the Los Angeles City Council, apart from the private parties and school treats, and these open-air celebrations give them plenty of scope for giving vent to their youthful exuberance with masks and fancy dresses, under adequate supervision. For the grown-ups there are dances galore, night club and hotel festivities, and cocktail parties, not forgetting a Jack-O-Lantern ball in aid of charity.
To-day quite a store of candy is waiting to be claimed at this address by the junior revellers when they make their appearance on Monday. Doubtless their tooth-and-jaw gymnasiums will work overtime, and in a number of cases result in a call on the family “medicine man” and the medicine chest at the close of the day.

Trick or Treat was a short-lived series on LWT (London Weekend Television), co-hosted by the English television and radio presenter Mike Smith (1955-2014) and the English comedian and author Julian Clary (born 1959). It was thus described by the journalist and critic James Green (1926-2015) in The Stage and Television Today (London, England) of Thursday 19th January 1989:

This new series, designed to kick of [sic] Saturday evenings with froth and fun, is described as the game show to end all game shows. It isn’t even bad enough to achieve that modest ambition and should carry a health warning.
I can imagine the scene at the company’s Thameside brain tank as someone points out that show is needed to rival the BBC’s Noel Edmonds series for the intellectually bereft.