Buzz
Building a habit is a classic life hack: You want to make a change in your life, so you add a new action to your daily schedule. Eventually, it becomes second nature—that’s the goal, at least—and then that aspect of your life runs on its own. But how much time does it actually take to build a habit? Contrary to what you may have heard, it isn’t always 21 days.
The time it takes to develop a new habit varies depending on the habit itself, your personality, and the techniques you use to create and sustain that habit. Scientific estimates have spanned from 21 days to as long as eight months or more. Let’s explore why this range is so broad and what you can do to speed up the habit-building process.
The myth surrounding the 21-day habit
The concept that it takes 21 days to develop a habit originated with Maxwell Maltz, a surgeon who observed that it took roughly three weeks for people to adjust to their new bodies following surgeries like amputations or plastic surgery, as noted by James Clear. (From my own experience with minor surgeries, I’ve found that it takes about two to three weeks for pain and swelling to decrease enough that you stop constantly thinking about the surgery; I can’t help but wonder if there’s a connection.)
The surgeon’s theory was that it takes 21 days for people to dissolve and re-create their ‘mental image’ of themselves. This idea isn’t supported by research; it’s just one person’s instinct. However, I think it resonated because it aligns with many of our personal experiences.
Let’s imagine you want to wake up early to exercise first thing in the morning. Sure, you can do it once. But how do you make it a consistent habit? When I was in that situation—trying to become a morning exerciser despite not being a natural morning person—I committed to sticking with it for an entire week before I even allowed myself to complain or change my plan. I had to be up at 6 a.m. every day, five days in a row, no exceptions. I looked forward to the break on the weekend, and by the second week, it felt easier. By the end of the third week, it had truly become my new normal.
Even though the 21-day rule lacks scientific evidence, it serves as a useful ‘trial run’ for a new habit. After all, one day could be a fluke. A week or two is a time period we’ve all been through before, and we can manage a disruption to our routine for that long (think of a vacation or a work deadline crunch). But by the time you reach three weeks, or ideally a full month, you’ve gained insights into how your new habit fits into your life. Even the simplest habits are never really simple; you need to learn and practice a variety of mini-skills while developing almost any habit.
By the time you hit that 21-day mark, you’ve probably repeated the action enough times. Crucially, you’ve likely encountered a few disruptions or challenges (like the weekend) and managed to get back on track. This timeframe is a good general guideline as it’s long enough to feel like ‘real life.’ But that doesn’t mean it’s sufficient.
Studies indicate that it takes several months for a habit to become automatic.
Scientific studies have tried to measure the time it takes for a habit to become truly automatic. For instance, this study had participants select a habit and link it to something they did once a day (such as 'eat a piece of fruit with lunch'). The study lasted 12 weeks. Some participants felt their new habit had become automatic after just a few weeks, while many others had not reached that point by the end of the study. The researchers concluded that most people would form an automatic habit somewhere between two and eight months...based on a model they calculated would apply to only 62% of participants.
That’s a broad range, and we don’t know if the other 38% of people would have ever reached a point where their habit was automatic. The researchers also discovered that simpler habits (like drinking water) became automatic more quickly than more complex ones (like doing 50 sit-ups).
A 2012 review looked at several other estimates and concluded that it would be more realistic to expect people to take at least 10 weeks for their new habit to become automatic. However, the review also emphasized that it’s helpful to know that any habit gets easier the longer you continue practicing it.
The authors point out that expecting a habit to form in 21 days can lead to discouragement. Instead, it’s better to focus on the long-term benefit of 'working diligently on a new behavior for 2-3 months.'
Speed up your habit formation with these techniques.
Time-based commitments can be a useful tool, like committing to the first week before making any changes to your plan or using your new moisturizer every day until the bottle runs out. However, another approach suggests that long-term behavior change is better understood through 'stages of change' rather than relying on set calendar dates.
At times, a habit may take longer to develop than anticipated. But thinking this way might allow you to establish the habit even sooner if you're deliberate in how you form it. Actively focusing on your new habit can also ensure its longevity, as we’ll discuss in the maintenance phase.
How to make a habit stick within the first 21 days
The initial phase of habit formation—whether you consider it to be 21 days, 30 days, or 66 days—is referred to as the action stage by behavior change psychologists. You’ve started the habit, but it’s not automatic yet, and you might still have doubts about your commitment. During this stage, you can improve your chances of sticking with the habit by following these steps:
Remember your reasons for doing it. For instance, place a reminder for your next dentist appointment on the bathroom mirror so you’ll recall not only that you should floss, but also the reason you want to floss in the first place.
Modify your environment to provide cues and support. For example, if your goal is to run every morning, lay out your running shoes the night before and have your partner check in with you about your run after you return.
Boost self-efficacy by acknowledging your progress. This could mean marking off the days you completed the habit on a calendar, working toward milestones (such as total miles run), or noting benchmarks of your improvement (maybe you could only do push-ups on a chair at first, but now you can do them on the floor).
Prepare for how you’ll maintain your habit even if you encounter interruptions (more on that shortly).
How to keep a habit going after the first 21 days
After building some momentum, you enter the maintenance phase. You’re doing the habit, and it might be starting to feel automatic, or at least more ingrained in your life. At this stage, you may need to consider the following actions:
Reassess your plan. Is running every morning still effective for you? Perhaps it’s better to lengthen some of the runs and designate certain days for rest, yoga, or strength training.
Anticipate any potential obstacles. If you go on vacation, will you maintain the habit? If something causes you to fall off track, how will you get back on it?
Ensure your motivation continues to work for you. For instance, if keeping up a streak on the calendar was highly motivating, the real challenge comes when you inevitably break that streak. At that point, something other than the streak should keep you going. This is often an intrinsic motivator: you enjoy being the kind of person who flosses daily, you’re excited to register for a race with your running buddy, or you’re proud that your cholesterol is lower thanks to your eating habits.
Building a habit isn’t about gritting your teeth until you hit a magical number of days. It’s an ongoing process that requires effort throughout, even five years down the road. Habits require work, but the ones that endure are those where the effort feels rewarding.
