Electricals retailer Dixons Carphone revealed Black Friday was the strongest trading day in its history as it said half-year profits surged by nearly a quarter.
The group hailed the one-day shopping bonanza as a "great start" to the Christmas season after it increased the number of Black Friday promotional deals by 30% compared to last year.
Dixons Carphone posted a 23% jump in underlying pre-tax profits to £121 million in the six months to the end of October on the back of increased sales of white goods and TVs, offsetting a fall in demand for tablets and PCs.
The firm - created following the £3.9 billion merger of Dixons and Carphone Warehouse last summer - added it continued to gain market share in the mobile phone market as a result of the collapse of rival Phones4U last year.
In the UK, it said earnings over the half-year period jumped 31% to £101 million and like-for-like sales lifted 7%.
Chief executive Sebastian James said: "This has been a very good first half for Dixons Carphone.
"Against a broadly flat market overall and a very strong comparative period we have seen continued like-for-like growth driven by market share gains across all territories."
He added: "A strong Black Friday was a great start to Christmas."
The half-year results came alongside the appointment of two retail veterans to the Dixons Carphone board.
Former BT chief executive Lord Livingston becomes deputy chairman and is joined by Tony DeNunzio, who was chief executive of Asda/Walmart UK, on the Dixons board.
Roger Taylor and John Gildersleeve will be stepping down from their roles after 17 and 15 years respectively.
Dixons Carphone's Black Friday plans were in contrast to o ther retailers, which cut back on the one-day promotions this year.
Supermarket Asda shelved the promotional day, saying it ate into trading in the crucial November and December Christmas period.
In its half-year figures, Dixons Carphone said it was encouraged by the early performance of trial stores launched as part of a joint venture agreement signed with US retailer Sprint earlier this year.
The venture currently has around 30 stores in America, but could grow to around 500 sites.
Dixons said it would make a decision on the wider roll-out early next year.
The firm, which runs stores in northern and southern Europe, said earnings fell 21% to £38 million in its Nordic region in the period, largely due the strong pound against the Norwegian krone.
It added that sales grew by 4% in southern Europe, although earnings were unchanged during the period at £1 million.
Mr James said: "I am particularly pleased to see progress in southern Europe despite a lively year in the Greek political and economic scene."
Shares in Dixons Carphone rose 3% after its half-year results.