A sale isn't worth it anymore unless you're getting 40% off

• Many retailers are extending holiday shopping discounts to record levels and for longer periods.
• Research firm LSEG says anything less than a 40% discount is just standard now.
• To get the best discounts, you might have to head to your nearest mall.

Americans set online spending records with sales totaling $9.8 billion on Black Friday and $12.4 billion on Cyber Monday, but more discounts spread over a longer period can make it trickier for consumers to find the best deals.

According to a report released in October from Adobe, which tracks online sales, retailers were expected to have record-high discounts for many common categories of gifts, especially around Black Friday and Cyber Monday. Many categories were expected to see unprecedented average discounts of as much as 35% for toys, electronics, apparel, sporting goods, TVs, appliances, and furniture.

But according to research from the London Stock Exchange Group, the number you should be looking for during the holiday season is 40%. The group notes that deep discounts are so common now that anything less is just a typical reduction seen throughout the year.

"Unless you are getting a 40% discount, you are just getting an everyday discount that you can get any other time of the year," said Jharonne Martis, London Stock Exchange Group's director of consumer research, during an appearance on November 27 on CNBC's "Worldwide Exchange."

And where can you find those 40% discounts? According to Martis, you are more likely to find those deals at department stores, apparel shops, and your local mall.

While Americans shelled out big during this year's shopping holidays, London Stock Exchange Group's research — in collaboration with Centric Market Intelligence — found the average discount this year on Cyber Monday was 38.4%, up from 37.6% on the same day in 2022.

Retailers have stretched out Black Friday and Cyber Monday shopping days into an entire week, or even longer, dedicated to deals. This might be an effort to get a head start on the sales and into your wallet sooner.

However, companies have also tried to spread out Black Friday's impact on their supply chains and operation costs, Kraig Foreman, shipping company DHL's supply chain e-commerce president, told CNBC's "Worldwide Exchange" on November 27. That worked in the last few years but didn't this year because financially stressed consumers became even more cost-conscious and looked for the best deals, he added.

"We actually saw softer sales year-over-year, coming into Friday, which was surprising," Foreman told CNBC. "Shoppers know what they want and know what they want to buy and were waiting for the best possible deal as they are trying to be really conscious with their money."

The good news is that these steeper discounts mean prices for popular holiday purchases have deflated from a year ago, according to the Wall Street Journal. For example, smartphones will cost 12% less on average, and TVs will cost 9% less.

Still, even though there are good deals, inflation is still heavy on the minds of shoppers this holiday season, forcing retailers to work harder.

"Inflation has definitely caused the consumer to become a bargain hunter," Martis said. "Retailers moved a lot of those sales earlier than usual, and then it became one big event culminating on Cyber Monday."