How to Build Lasting Habits with the 21/90 Rule

Have you ever tried to build a habit but gave up after a few days? If yes, this blog is totally for you! Don’t worry, you’re not alone!

What if I told you there’s a simple rule—the 21/90 Rule? It’s a game-changer for habit formation. Let’s dive in and learn more about it.

What is the 21/90 Rule?

The 21/90 Rule is a straightforward strategy to make habits stick. Here’s how it works:

• 21 days to form the initial habit. This is the ‘getting started’ phase— the foundation of your habit.
• 90 days to stick to the habit, where it becomes part of your lifestyle and it’s harder to break.

I have a short story about this. When I was in 4th grade, my English teacher (she was my favorite, by the way) told us that when you do something for 21 days, it naturally becomes your habit. I was a bit lazy about brushing my teeth at night. But after she told us about this rule, I started brushing regularly, and since then, it has become part of my daily routine. Now, I find it impossible to sleep without brushing my teeth.

This rule is grounded in the science of habit formation. It helps you focus on small, achievable milestones and keeps you motivated throughout the process.

Step 1: Set a Clear and Achievable Goal

Before jumping into the 21/90 Rule, it’s important to define exactly what habit you want to build. Whether it’s drinking more water, exercising regularly, journaling every day, or eating healthier, clarity is key! (Checkout this journal from Amazon )

For example, if you want to make exercise a habit, you could start with a simple goal like, “I will work out for 15 minutes every day for 21 days.”

Make sure your goal is realistic. It’s better to start small and gradually increase your commitment rather than setting yourself up for failure with an overly ambitious goal.

Step 2: Stick with It for 21 Days

The first step of the 21/90 Rule is committing to the habit for 21 consecutive days. This is the time it takes for your brain to start associating the new action with your routine.

Tips for success during the 21 days:

• Track Your Progress: Use a habit tracker or journal to monitor your progress. It’s a great way to stay motivated and see how far you’ve come!( Planner that you’ll absolutely love!)
• Make It Simple: Keep the action as simple as possible during this phase. The goal is to form the habit, not to push yourself too hard.
• Consistency Is Key: Try to do the habit at the same time every day. Consistency builds familiarity, and that’s what makes a habit stick.

Step 3: Build on the Habit for 90 Days

You’ve made it through the first 21 days—awesome! But here’s the thing: the 21/90 Rule doesn’t stop there. To turn that habit into a lifestyle, you’ve got to keep going for 90 days.

This is where your brain starts to rewire itself. After 90 days, your new habit won’t feel like something you’re forcing yourself to do—it will feel like a natural part of your routine. It’ll just click.

During this phase, it’s time to gradually increase the challenge a bit:

• If you’ve been working out for 15 minutes, increase it up to 20 or 30 minutes.
• If you’ve been drinking more water, aim to increase your daily intake.
• If you’ve been journaling, challenge yourself to write longer or more deeply.

The goal here isn’t to make it harder just for the sake of it—it’s about making sure the habit becomes more fulfilling and impactful.

Why Does the 21/90 Rule Work?

The 21/90 Rule works because it follows the science of habit formation. In the early stages, it’s all about repetition and consistency. Once you get to 90 days, the habit becomes automatic and starts to require less mental energy.

Your brain creates neural pathways that make the habit feel like second nature. This process is why some people say that the first 21 days are the hardest—but it gets easier after that!

Tips for Success with the 21/90 Rule

Start small, stay consistent: Rome wasn’t built in a day, and neither are lasting habits. Focus on making the habit small and easy to stick to in the beginning.

Track your progress: Whether it’s a habit tracker, journal, or simple checklist, tracking helps you stay motivated and see how far you’ve come.

Be kind to yourself: Missed a day? That’s okay! Just pick up where you left off. Perfection isn’t the goal—consistency is.

Celebrate small wins: Every time you hit a milestone (like 30 days, 60 days, or 90 days), celebrate! This reinforces the positive feeling of making progress.

Find accountability: Tell a friend or share your goal online. Having someone to check in with can make a huge difference in staying on track.

Looking for a deeper dive into habit formation? Check out Atomic Habits by James Clear. Or The Power of Habit by Charles Duhigg It’s packed with strategies to help you create habits that truly stick.

Final Thoughts

Building lasting habits isn’t about willpower or overnight success—it’s about patience, consistency, and the right approach. The 21/90 Rule is a simple yet powerful tool that helps you start small, stay consistent, and turn new behaviors into lasting changes.

So, what habit are you ready to build? Share it with me in the comments! I’d love to hear about your journey, and remember—you're not alone in this.

Here’s to making positive changes, one day at a time!

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