Other brands running ads in national newspapers include H Samuel, Debenhams, Tesco and Game.
Currys PC World placed six ads in The Sun promoting deals for electrical goods and kitchen appliances, calling it "our biggest black Friday ever".
Black Friday is the day after Thanksgiving in the US, where it is seen to kick off Christmas shopping.
The phenomenon has travelled over the Atlantic, and some retailers in the UK began their deals at midnight.
The ads dominate today’s tabloid papers, with many incorporating black into their branding.
The Very.com press ad shows a black liquid seeping over the bright pink it uses for the brand. Boots has decorated its usual ad with a border of black sequins.
Littlewoods.com is launching a new deal every hour, focusing on different brands such as Samsung, Sony and LG.
Debenhams is offering VAT-free prices on fragrances, and half price on other items including clothing and electrical.