So, it pays to know when your particular store might be quietest, when staff will have restocked the shelves and when items get marked down for the best yellow sticker bargains.
With nearly 30% of Brits admitting Christmas food shopping is their holiday nightmare, Britsuperstore has analysed the UK's top 10 supermarket chains to find the perfect times to do your Christmas shopping at each one.
Reductions: Before 8am and before closing (fresh produce with red stickers typically discounted 30-75%)
The exact time of day for reductions will vary from store to store, but most will happen just before the store closes. Fresh products with reduced prices will be marked by a red sticker, and are typically reduced as they are at the end of their shelf life. They will normally be discounted by either 30% or 75%. Dried groceries and tinned food may also be discounted if they have imperfections.
Reduction: Morning and before closing (they have a two-wave reduction system, first thing in the morning and a few hours before closing)
Again, the schedule for price reductions varies from store to store, but the majority of branches operate on a two-wave basis. Products are reduced first thing in the morning and a few hours before the store closes, although some stores may opt to make reductions throughout the day based on the volume of stock and sell-by dates.
Reduction: Starts at 3pm (50% off for near-expiry items), followed by a further reduction at 5pm (75% off) with final dramatic reductions on in-store cooked food at 8pm (schedule may vary)
Morrison stores typically have several waves of price reductions. Reductions begin at 3pm, with products at the end of their shelf life reduced by 50%. At 5pm, these products are reduced again, retailing at 75% of their original price. If you're looking for a bargain on in-store cooked food, we recommend visiting the store at 8pm, as items will be dramatically reduced. Remember, the schedule for reductions may vary depending on the branch.
Reduction: Starts around 6pm (50% off for expiry-date items), with a possible further reduction at 8pm (schedule may vary)
Visit your local Co-op at around 6pm to be sure of a discount, although, at some stores, reductions start at 5pm. Items on sale on the day of their expiration date will usually be sold at 50% of their original price
Reduction: Starts at 9am (around 10% off), with further reductions between 4-5pm (around 30% off). Best reductions around 8pm (schedule may vary)
At around 9am, items are reduced by around 10%. Some products are reduced further between 4pm and 5pm, by about 30%. For the best reductions, visit about 8pm, but again, keep in mind discount schedule may vary by store.
Reduction: Starts after lunch (biggest discounts between 5-7pm) with significant variations by store (check with your local store)
Reduction times at Sainsbury's varies significantly by store. Make sure to visit after lunch, as this is when most stores begin to reduce their products. The best time to visit is between 5 pm and 7 pm, as this is when the biggest discounts will happen.
Busiest: Monday-Friday 5-6pm, Saturday 1pm, Sunday 12pm
Quietest: Monday 6-8am and 10-2pm, Tuesday-Friday 10pm-7am, Saturday 12-7am, Sunday 11am and 4pm
Reductions at ASDA typically begin between 6 am and 10 am. There is a second round of reductions takes place at about 5 pm, and final reductions begin at around 7:30 pm. Again, discount schedules may vary from store to store.
At most Marks & Spencer stores, there are three waves of reductions. The first wave takes place around 9 am, where some items may be reduced by 10%. The real reductions, however, begin around 2 pm. Here, products are normally reduced by 30%. The final wave of reductions happens after 4 pm, where products are reduced between 70% and 90%.
The majority of Waitrose branches begin to reduce their products just after the lunchtime rush. For the best shot at reduced items at the best price, however, we recommend visiting stores two hours before closing time, when some stock, and in particular fresh food, is reduced by around 50%.
Reduction: Added to deliveries, plus flash discounts and schemes (check local store)
At Iceland, reductions are added to deliveries. Iceland also offers "flash discounts", and discount schemes, so be on the lookout for these. Last year, for example, they announced a scheme which allowed customers over the age of 60 to get 10% off their groceries with no minimum spend every Tuesday.
Remember: Reduction schedules may vary by store for every chain, so always check with your local branch.
Richard Price, Director of Britsuperstore, an online supermarket which specialises in food for expats, shares his seven tips to save this Christmas.