That includes chocolate like Coffee Crisp, KitKat, Caramilk, Mars and Twix, candy like Twizzlers, Swedish Berries and Sour Patch Kids and chips like Ruffles.
Narcity went to all three stores, looked for similar products, checked prices and then compared costs.
So, here's what you need to know about the Halloween candy, chocolate and chips and which store has the cheapest products.
Coffee Crisp, KitKat, Aero and Smarties
Coffee Crisp, KitKat, Aero and Smarties at Costco. Centre: Coffee Crisp, KitKat, Aero and Smarties at Walmart. Right: Coffee Crisp, KitKat, Aero and Smarties at Loblaws.
All three stores have packs of Coffee Crisp, KitKat, Aero and Smarties chocolate, but Costco has full-sized bars, while Walmart and Loblaws have treat-sized bars.
It costs $21.99 for a 1.08-kilogram box of 24 full-sized bars at Costco, which works out to $2.03 per 100 grams and $0.91 per chocolate.
It costs $15.97 for a 977-gram box of 100 treat-sized bars at Walmart, which is $1.63 per 100 grams and $0.15 per chocolate.
It costs $24 for a 977-gram box of 100 treat-sized bars at Loblaws, which breaks down to $2.45 per 100 grams and $0.24 per chocolate.
Walmart is $0.40 cheaper per 100 grams than Costco and $0.82 cheaper per 100 grams than Loblaws for this product.
Caramilk, Dairy Milk Oreo and Twirl
Dairy Milk Oreo, Cadbury Toffee Crunch, Twirl and Caramilk at Costco. Centre: Dairy Milk Oreo, Caramilk, Wunderbar and Twirl at Walmart. Right: Dairy Milk Oreo, Caramilk, Wunderbar and Twirl at Loblaws.
These stores have the Cadbury treat-size bar variety pack with Caramilk, Dairy Milk Oreo and Twirl chocolate, but Costco includes Cadbury Toffee Crunch, while Walmart and Loblaws include Wunderbar.
It costs $17.99 for a 1.3-kilogram box with 120 chocolates at Costco, which breaks down to $1.38 per 100 grams and $0.14 per chocolate.
It costs $15.48 for a 993-gram box with 90 chocolates at Walmart, which works out to $1.55 per 100 grams and $0.17 per chocolate.
It costs $22 for a 993-gram box with 90 chocolates at Loblaws, which is $2.21 per 100 grams and $0.24 per chocolate.
Costco is $0.17 cheaper per 100 grams than Walmart and $0.83 cheaper per 100 grams than Loblaws for this product.
Ruffles chips
Ruffles chips at Walmart. Right: Ruffles chips at Loblaws.
Both Walmart and Loblaws have boxes of snack-sized Ruffles chips.
It costs $12.97 for a 640-gram box of Ruffles chips with 40 snack-sized bags at Walmart.
It costs $12.99 for a 640-gram box of Ruffles chips with 40 snack-sized bags at Loblaws.
Walmart is $0.02 cheaper than Loblaws for this product.
Mars, Twix, Snickers and peanut M&M's
Mars, Twix, Snickers and peanut M&M's at Costco. Right: Mars, Twix, Snickers and peanut M&M's at Walmart.
Both Costco and Walmart have the treat-sized Mars, Twix, Snickers and peanut M&M's chocolates for Halloween.
It costs $23.99 for a 1.48-kilogram box with 140 treat-sized chocolates at Costco, which works out to $1.62 per 100 grams and $0.17 per chocolate.
It costs $14.97 for a one-kilogram box with 95 treat-sized chocolates at Walmart, which breaks down to $1.49 per 100 grams and $0.15 per chocolate.
Walmart is $0.13 cheaper per 100 grams than Costco for this product.
Twizzlers
Twizzlers at Costco. Centre: Twizzlers and Jolly Rancher gummies at Walmart. Right: Twizzlers and Jolly Rancher gummies at Loblaws.
Each store has treat-sized Twizzlers, but the Costco pack has more flavour varieties, while the Walmart and Loblaws packs have Jolly Rancher gummies.
It costs $14.99 for a 1.3-kilogram bag with 109 pieces at Costco, which works out to $1.15 per 100 grams and $0.13 per piece.
It costs $12.97 for a 1.02-kilogram bag with 100 pieces at Walmart, which is $1.27 per 100 grams and $0.12 per piece.
It costs $20 for a 1.02-kilogram bag with 100 pieces at Loblaws, which breaks down to $1.96 per 100 grams and $0.20 per piece.
Costco is $0.12 cheaper per 100 grams than Walmart and $0.81 cheaper per 100 grams than Loblaws for this Halloween candy.
Reese's, Oh Henry, Hershey's Cookies 'n' Creme and Whoppers
Reese's, Oh Henry, Hershey's Cookies 'n' Creme and Whoppers at Walmart. Right: Reese's, Oh Henry, Hershey's Cookies 'n' Creme and Whoppers at Loblaws.
Walmart and Loblaws have bags of Reese's Cups, Reese's Pieces, Oh Henry, Hershey's Cookies 'n' Creme and Whoppers chocolate for Halloween.
It costs $12.97 for a 962-gram bag with 100 chocolates at Walmart.
It costs $20 for a 962-gram bag with 100 chocolates at Loblaws.
Walmart is $7.03 cheaper than Loblaws for this product!
Swedish Berries and Sour Patch Kids
Swedish Berries and Sour Patch Kids at Costco. Right: Swedish Berries, Sour Patch Kids, Fuzzy Peach and Swedish Fish at Loblaws.
Costco and Loblaws have Halloween candy boxes with Swedish Berries and Sour Patch Kids, but the Loblaws pack also has Fuzzy Peach and Swedish Fish.
It costs $23.99 for a 1.9-kilogram box with 150 pieces at Costco, which breaks down to $1.26 per 100 grams and $0.15 per piece.
It costs $19 for a 1.12-kilogram box with 90 pieces at Loblaws, which is $1.78 per 100 grams and $0.21 per piece.
Costco is $0.52 cheaper per 100 grams than Loblaws for this Halloween candy.
Cheetos
Cheetos at Walmart. Right: Cheetos at Loblaws.
Walmart and Loblaws have boxes of snack-sized Cheetos for Halloween.
It costs $12.97 for a 640-gram box with 40 snack-sized bags at Walmart.
It costs $12.99 for a 640-gram box with 40 snack-sized bags at Loblaws.
Walmart is $0.02 cheaper than Loblaws for this product.
WHICH STORE HAS THE CHEAPEST HALLOWEEN CANDY?
Now that we've compared prices for eight Halloween candy, chocolate and chips at Costco, Walmart and Loblaws, let's break down which store has the lowest prices.
Costco is the cheapest store for the box of Dairy Milk Oreo, Cadbury Toffee Crunch, Twirl and Caramilk, the bag of Twizzlers and the box of Swedish Berries and Sour Patch Kids.
Walmart is the cheapest store for the box of Coffee Crisp, KitKat, Aero and Smarties, the box of Ruffles, the box of Mars, Twix, Snickers and M&M's, the bag of Reese's, Oh Henry, Hershey's Cookies 'n' Creme and Whoppers, and the box of Cheetos.
None of the Halloween candy, chocolate or chips at Loblaws that Narcity compared have the lowest prices.
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