You move to a new city. You meet a few people you like. A year later, you still don't have anyone you'd call at midnight. It's easy to decide you're bad at friendship.
The communication researcher Jeffrey Hall at the University of Kansas had a simpler explanation: you probably haven't spent enough time together yet. In 2018 he asked a plain question, "How many hours does it take to make a friend?", and got an answer.
Hall surveyed 355 adults who had recently moved and were looking for friends, and separately followed 112 first-year university students over their first weeks. Pulling both studies together, he estimated roughly:
Not all hours were equal. Time spent hanging out, joking around or playing games built closeness. Hours spent working side by side counted for much less. And hours weren't everything: in the student study, certain kinds of everyday talk also predicted friendships growing closer.
You don't find close friends. You accumulate them, a couple of hours at a time.
Pick a pattern, or set your own hours a week with one person.
Uses the midpoints of Hall's ranges (50, 90 and 200 total hours together since meeting) and assumes that time is mostly social rather than work. These are rough averages from two studies, not a guarantee. Some friendships click faster; some never do.
School and university handed out friendship hours for free. You saw the same people every day, without planning it, for years. Researchers have known since a 1950 study of student housing at MIT that sheer closeness predicts friendship: residents living near the stairways ended up with more friends on other floors, simply because they bumped into more people.
Adult life removes most of that. People move, work longer hours, and spend weekends on partners, children and errands. Friendship stops being a side effect of where you are and becomes something you have to schedule.
Underestimating how much people like you. In a 2018 set of studies, strangers getting acquainted in a lab, and new university housemates over several months, consistently thought their partners liked them less than they really did. Researchers called it the liking gap. If you've been waiting for clearer signs of interest before following up, you may already have them.
Not reaching out. In 2022, a series of experiments found that people consistently underestimate how much others appreciate a quick check-in message or a small gesture, and the gap was biggest between people who weren't already close. The "they'll think it's weird" fear is mostly wrong.
Adult friendship isn't a talent; it's mostly a matter of time together. Jeffrey Hall's research suggests roughly 50 hours to become casual friends, about 90 to become friends and more than 200 to become close friends, with social time counting far more than work time. School supplied those hours automatically; adulthood doesn't. People also like you more, and appreciate your reaching out more, than you're likely to assume.
Try this: pick one person you already enjoy. This week, suggest one recurring thing, the same café every Thursday or a weekly walk, and put the first three dates in your calendar.
Sources. Hall, J.A. "How many hours does it take to make a friend?" Journal of Social and Personal Relationships, 2018 (hour ranges and the work-time finding as reported by the University of Kansas, March 2018). Festinger, Schachter & Back's 1950 Westgate studies at MIT on proximity and friendship. Boothby, E.J. et al. "The Liking Gap in Conversations." Psychological Science, 2018. Liu, P.J. et al. "The surprise of reaching out: Appreciated more than we think." Journal of Personality and Social Psychology, 2022.