The best times of year to buy expensive electrical goods have been revealed by consumer watchdog Which? – and Black Friday (which falls on November 23 this year), Boxing Day and the New Year sales might be your best bet for a bargain after all.

A year-long investigation tracked the prices of 32 of the most popular makes and models of home and tech appliances across five major retailers: Amazon, AO.com, Argos, Currys PC World and John Lewis.

It found prices really do fluctuate considerably throughout the year, with one item sometimes retailing at 54 per cent more than its sale price – the Vax Blade 32v vacuum cleaner cost £299 at its highest point at online retailer AO.com, but came down to £139 at its cheapest.

So, to avoid being ripped off when you’re next buying a TV, vacuum cleaner or washing machine, these are the best times to buy.

If you need a new TV, smart speakers or a washing machine, the best time to buy is Black Friday, Christmas and New Year, Which? revealed.

Electric toothbrushes and digital cameras are best bought at Christmas, New Year or Easter, while printers and vacuum cleaners should be purchased in the spring. Buy your fridge-freezer in either spring or summer (just in time to cram it with ice cream).

Items such as fitness trackers, ovens, cordless phones and kettles tend to have more sporadic price drops, so Which? advised keeping snapping them up “any time there’s a good discount”. 

The analysis found that Amazon adjusted its prices the most and offered the lowest prices more often than the other retailers throughout the investigation. In contrast, Currys PC World had the highest number of most expensive prices.

A spokesperson for Currys said: “While our prices – like all retailers – can fluctuate throughout the year, we’re proud to offer our Price Promise across our entire range. We also offer our customers pricing transparency by stating in all our channels exactly when a product was available for a higher price, unlike most retailers.”

Alex Neill, managing director of home products and services at Which?, advised shoppers to “take retailer hype with a pinch of salt”. Don’t feel pressured by time-limited sales and do your research before buying, he added. 

Advice for shopping in the sales

• Look at the price instead of the advertised ‘saving’. Big discounts can sometimes be exaggerated to make the deal look better than it really is.

• Check the retailer’s returns policy before buying. Don’t assume you can return a sale item that you change your mind about.

• Shop at retailers with price promises, which may ensure you can get a part-refund if your item drops in value in the weeks following your purchase.