It chose the women's title because of the A5 size of its monthly magazine, Glamour, which is designed to fit in readers' handbags.
As part of the promotion, Baileys Minis will feature on the site's daily email newsletter to 14,000 subscribers, alongside suggested affordable luxuries. It will also sponsor the site's 2003 style preview section.
Skyscraper ads will direct users to a mini must-haves page, which suggests 10 items and accessories this season, including Love Heart sweets and Molton Brown travel kits.
Baileys launched its single-serving Minis at the start of the month.
It is enticing women to keep the gold-coloured, mini-bottles in the fridge to treat themselves after work or with friends, and in turn increase home consumption.
PR agency Countrywide Porter Novelli booked the promotion on behalf of Baileys.
In April, Baileys teamed up with Glamour.com to support its sponsorship of Channel 4 favourite Sex and the City.
The web site hosted a Sex and the City-related competition offering users the chance to win a pair of designer Manolo Blahnik shoes.
Serena Privett, senior account manager at Conde Nast Online, said: "Baileys' association with Sex and the City shows that it's a stylish brand, and the previous competition we ran worked so well that the programme was keen to do more."