Blank Street Coffee has introduced a subscription program called Blank Street Regulars to attract regular coffee drinkers. The startup has grown rapidly to 74 locations across New York, Boston, Washington D.C, and London in 3.5 years since launching. The program charges $8.99 or $17.99 weekly for unlimited drinks, up to 14 per week. It currently has around 5,000 members and another 4,000 on the waiting list. Blank Street estimates subscriptions could eventually make up 30-40% of its customer base.