The firm, which provides fashionable twenty-somethings in 160 different countries with copies of their idols' wardrobes, despatched two million orders in December while sales rose to just under £80 million.
Online retail store ASOS has remained on trend after demand for celebrity-inspired fashion drove a 40% year-on-year increase in revenues last month.
ASOS, which stands for As Seen On Screen, said the rush for onesies, the all-in-one adult pyjamas worn by public figures including Cheryl Cole to Nick Clegg, helped sales rise by a bigger-than-expected 34% in the UK.
Trends such as bold jewellery, as worn by Beyonce, and 'baroque', the lavish, gold-embroidered trend that flooded catwalks last autumn, were also big sellers.
According to chief executive Nick Robertson, cutting prices to match budget brands such as Primark played a significant role in the performance. He added: "Our twenty-something customer isn't any wealthier than a year ago so adjusting our prices was key."
ASOS also attributed much of the increase in traffic to social media initiatives such as 'shoppable films', where viewers can click on and purchase items while watching promotional videos. The videos, posted on sites including Facebook and YouTube, feature celebrities such as Ellie Goulding and Azealia Banks.
Mr Robertson said: "Social media is an important factor for us - not just promoting and connecting but making it easier for the customer."
He added that simplifying delivery services, with customers now receiving a text with the delivery time and courier's name, have also acted as an incentive for customers.
The company said the rise in international sales was "fundamental" to its performance, with local language websites in China and Russia a "significant step" in becoming the top retail website for the young and chic globally.
The 40% rise in active customers to 5.6 million on a year earlier should spark a rise in employment, with the company currently having 1,500 people at its Barnsley warehouse.