Britain’s online retailers won the battle for sales on Black Friday with overall spending up on a year ago despite a drop in the number of shoppers visiting stores.

As the annual shopping jamboree kicked off, a dip in web traffic figures and fewer shoppers out on the high streets suggested Britons were falling out of love with the American-inspired discount day. But momentum built during the day and Barclaycard, which processes nearly half of all debit and credit card transactions in the UK, estimated that Black Friday spending finished up 8% on 2016.

John Lewis described the promotional bonanza as “one of its most successful days”. The department store chain said it had its busiest ever single hour of online trading, but that it was too early to say if a sales record had been set.

Dino Rocos, the retailer’s operations director, said: “Sales on Johnlewis.com both overnight and into the day itself have exceeded expectation. We expect traffic will continue to the website throughout the weekend.”

While sales were strong online, fewer shoppers hit the high street than last year, continuing a long-term change in habits. Three years ago police and ambulances were called to major supermarkets as near-riots broke out among shoppers desperate to grab bargains. But this year the supermarkets either opted out of the event or had only limited deals available. Yesterday at a branch of Currys/PC World on London’s Oxford Street, the doors were flung open at 7am and only one shopper, who had pre-ordered a laptop, was waiting.

By mid-afternoon the number of visitors to shopping centres, retail parks and high streets across the country was down 8% as analysts said more than a week of previous discounting by fashion and electrical goods chains had spread demand.

“It was not Black Friday but mid grey week,” said Diane Wehrle of shopper traffic measuring firm Springboard. “With the budget this week and concerns about the economy, people are feeling fairly cautious about spending money on stuff they possibly don’t really need.”

John Lewis said the most popular product searches were for iPads and Sonos speakers, suggesting these are among the most sought after gifts this Christmas. But shoppers also bought sofa beds and expensive perfume such as Creed, which costs £207 a bottle.

Argos said more than 2 million people visited its website in the four hours after it launched its Black Friday deals on Thursday night. “These early record-breaking figures show that savvy shoppers are keen to bag themselves a bargain in the run-up to Christmas,” said John Rogers, the Argos chief executive. “People are clearly buying their big Christmas presents, as we’ve seen a real spike in sales of video games and consoles as well as iPads and TVs.”

Shoppers were predicted to spend more than £2.5bn on Black Friday itself. The number of shoppers online between midnight and 7am was 24% lower than last year, according to the e-commerce trends service PCA Predict, after an 11% rise in shopping over the previous week. But by 5.30pm the number of shoppers was up 3% year on year.

“This longer sales period has shifted the emphasis away from Black Friday being a major retail event in its own right, towards becoming part of a pre-Christmas mini-season or ‘golden quarter’ for retailers,” said Chris Boaz, ‎the head of marketing at PCA Predict.

While Friday morning was quiet, Boaz said there had been a huge surge in online sales on Thursday evening as people tried to beat the rush to snap up the best deals.

John Lewis admitted its online store had crashed for a short period as shoppers searched for bargains and as the department store price-matched rivals’ early Black Friday offers. Video games specialist Game also admitted to some problems with its checkout service after its deals launched on Thursday night as gamers raced to get their hands on a Nintendo Switch.

With household finances tight this year, retailers are hoping a discount frenzy will persuade shoppers to open their wallets.

The high-street clothing retailer Next, which traditionally refuses to offer pre-Christmas discounts, entered the Black Friday fray for the first time to boost flagging sales.

The analyst Tony Shiret said Next’s offer of 70% off all Black Friday lines showed the retailer was struggling to clear stock in its usual end-of-season sales.

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