How Long Should You Bulk For? 3 Factors To Consider

If you bulk too long, you risk adding more body fat than necessary, which will make it harder when you start your cutting cycle.  

On the other hand, if you don’t bulk long enough, you’ll be limiting the amount of muscle mass you gain while eating in a caloric surplus.

So, how long should you bulk for? 

The length of your bulk should be a minimum of 4 weeks and can last more than 12 weeks. An aggressive bulk phase (i.e. dirty bulk), where you’re okay gaining more fat in the process, can be 4 to 6 weeks.

A conservative bulk phase (i.e. lean bulk), where you want to minimize fat gain, should last at least 12 weeks.

Before you can determine how long you should bulk for, you need to understand which approach to bulking is best for you and if your bulking goal is realistic.

Key Takeaways

  • Before determining how long you should bulk, you should first make sure you’re in a good place to start a bulking phase. Men should have less than 15% body fat and women should have less than 20% body fat before starting a bulk.
  • Gender doesn’t affect how long you should bulk, as the more important factors that determine the length of a bulk are the type of bulk you’re doing and how happy you are with your progress.
  • Regardless of how long your bulk lasts, you should eat at maintenance for at least 2 weeks before cutting to give your body time to adjust to your new weight and avoid potentiailly decreasing your calories too much during your cut.

What To Consider Before You Decide To Bulk

1. Current Body Fat Percentage

Ideally, men should have less than 15% body fat and women should have less than 20% body fat before bulking.

Leaner individuals are more likely to gain muscle instead of fat during a bulk. If you try to bulk when your body fat percentage is higher than the numbers above, you’re more likely to gain more fat than muscle.

Starting a bulk from a leaner state also ensures you don’t gain too much fat that will be harder and take longer to lose in the future.

2. Your Mental and Emotional State

Intentionally gaining weight can be a scary thing for many people to wrap their heads around. This is especially true for women, who are often told by the media and society as a whole that they constantly need to be shrinking their bodies.

Before you start a bulk, make sure you’re in a good state of mind and mentally and emotionally prepared to handle increases on the scale or your clothes fitting tighter.

3. Your Relationship With Food

Bulking may sound enjoyable because you get to eat a lot of food. However, if you were previously restricting food groups or constantly trying new diets to lose weight, you may have developed a poor relationship with food.

This ties into the previous point as well, but making sure you are mentally and emotionally prepared to eat more calories while still prioritizing your health is important.

If you want to use a bulk to justify binging on food that you otherwise would restrict yourself from eating, consider eating at maintenance for a while first while allowing yourself to enjoy a few treats on occasion.

You’ll be less likely to unintentionally fall into a dirty bulk where you over-consume foods you don’t usually allow yourself to eat and gain more fat than you want.

How Many Weeks Should Your Bulk Be? 

Your bulk should be at least 4 weeks to see any significant changes, but the average bulk lasts between 8 to 16 weeks because this is the length of time it takes to see significant results in muscle gain. 

A bulk could last longer than 16 weeks if you still wanted to progress in your bulk. A longer bulk is best for those who are lean bulking (adding mass while staying as lean as possible) because progress will be much slower with this approach. 

I wrote another article on lean bulking.  Check it out if you want a step-by-step approach on how to lean bulk using a conservative approach.   

A shorter bulk is probably more reflective of those who are dirty bulking (adding mass quickly with no concern for fat gain). This is because you will add mass so quickly that it won’t take very much time to see the results you’re looking for.

You may want to do a dirty bulk if you need to add mass as fast as possible, whether it’s for personal preference or to compete in a higher bodyweight category for a weight-class sport like powerlifting or weightlifting.

3 Factors That Determine The Length Of Your Bulk

3 factors that determine the length of your bulk

The length of your bulk depends on:

  • Your bulking approach
  • How your body is responding
  • How far you are from your goal

1. Your Bulking Approach

The length of your bulk will mostly depend on the bulking approach that you choose to work towards your goal.

The bulking approaches are:

  • Lean Bulk: reducing fat gain as much as possible while gaining muscle.
  • Standard Bulk: accepting some fat gain while gaining muscle.
  • Dirty Bulking: gaining a significant amount of fat while gaining some muscle.

Lean Bulk

If you choose to lean bulk and take a more slow and steady approach then this will involve smaller increases in calories above your maintenance (the number of calories it takes for you to maintain your weight).

Generally, for a lean bulk, you would increase your calories by 100-200 calories weekly or bi-weekly and continue monitoring your body weight and body composition to see how your body responds.

If you’re gaining more fat than you’re comfortable gaining, then you may want to keep your calories the same and wait for your body weight to stabilize before increasing again.

The smaller increase in calories above maintenance will allow you to bulk for a longer period to try and gain more muscle with little to no fat gain. 

With a lean bulk, it’s best to stay in this phase for more than 12 weeks to see the best results, any less than this likely won’t be enough time to gain a significant amount of muscle because the calorie increases are smaller and therefore will require more patience.

Standard Bulk

A standard bulk is a moderate approach to bulking where there is some potential for fat but there is also greater potential for muscle gain. This is the most common approach that people take when bulking.

With this approach, you will increase your calories by 200 to 300 calories every week or every two weeks depending on how your body is responding.

If you feel that you’re gaining too much fat too quickly, then you can reduce the frequency at which you’re increasing your calories.

Those who are doing a standard bulk should be in this phase for 8 to 12 weeks.  

Most people who are new to bulking, i.e. they’re trying their first bulking phase, should plan to spend this amount of time bulking.

Dirty Bulk

If you choose to do a dirty bulk, then you will gain weight more rapidly but it won’t necessarily be muscle because calories will increase so quickly that the potential to gain fat is high.

When dirty bulking, calories are generally increased by 300+ calories weekly or bi-weekly, which speeds up the bulking process.

For the best results with dirty bulking, you should bulk for at least 4 weeks to give your body enough time to add mass, but it’s not recommended that you continue to dirty bulk beyond 6 weeks. 

This is because, after 6 weeks, you will have put on a significant amount of fat mass and very little muscle mass because you can only gain so much muscle in such a short time frame but the potential to gain fat mass is very high.

Therefore after 6 weeks, you’ll have gained a significant amount of fat compared to muscle, which is likely not your end goal if you want to be strong, jacked, and healthy.

It should also be noted that the term “clean bulking” is used to describe a bulk that revolves entirely around nutrient-dense whole foods, but does not represent how aggressive you’re being with your bulk.

You could do a clean bulk while bulking conservatively or aggressively, but it’s probably much harder to eat “clean” while bulking aggressively without getting too full.  

This is why many people turn to sugar and other calorie-dense foods while dirty bulking. 

2. How Your Body Is Responding

Another important factor that will contribute to how long you should bulk is how well your body is responding to the approach that you’re taking.

If you’re not progressing as quickly as you had hoped while bulking, then it may take you longer than expected to reach your goals.

If you’re progressing much faster than you expected, then you may end your bulk earlier than expected.

Perhaps you had planned to spend 10 weeks in a moderate bulk, but after 7 weeks you feel like you’ve achieved your desired results; at that point, it’s okay to end your bulk early.

Or maybe you find that the approach that you chose initially isn’t achieving your desired results, and therefore you’ll have to change your approach.

If you started off with a conservative approach but didn’t see a significant amount of progress, then it’s probably best that you take a moderate or dirty bulk approach instead.

Or if you started with a dirty bulk approach and then gained fat way too quickly for your comfort level, then you may want to scale back and take a more moderate approach instead.

In theory, there are set timelines based on how you choose to bulk but in reality, your body is going to respond at its own pace.

3. How Far You Are From Your Goal

The last factor that you need to consider about the length of your bulk is how far you are from your bulking goal.

When your goal is loftier, then the process is going to be longer and you may not be able to achieve it with just one bulking cycle.

For example, if your goal is to gain 30 lbs of muscle, then it will take you multiple bulking cycles throughout the year to get there.

If you tried to gain 30lbs of muscle all in one bulk and didn’t take breaks then you would gain much more fat than you probably want to along with the muscle if you’re doing a standard or dirty bulk. 

Coming back to maintenance calories in between these bulking cycles will give your body a chance to regulate itself by re-distributing some of the fat you’ve gained (from purely in the stomach area to more evenly distributed) or perhaps you might even lose some fat and retain muscle as you go back to maintenance.

With a lean bulk, your body would just become less and less responsive over time, making it harder to put on muscle as readily if you didn’t take breaks back to your baseline (maintenance) for your body to regulate itself.

Does Gender Affect How Long Should A Bulk Be?

Gender does not affect how long a bulk should be. However, men and women gain muscle at different rates.

So while the guidelines for determining the length of a bulk are the same regardless of gender, men and women can’t expect to gain the same amount of muscle mass, even if their diets and training routines are the same.

Men naturally have more testosterone than women. Testosterone is the hormone responsible for bone density, muscle strength, and muscle mass. Since men have more testosterone than women, it makes sense that they can gain muscle mass more easily.

I’ll provide estimates on how much muscle mass men and women can expect to gain from a bulking cycle in the following section.

Results That You Can Expect From Your Bulking Cycle

It’s important to be realistic about what results you can expect from a bulking cycle so that you know what goals to set and you’re not disappointed.

Realistic muscle gain expectations for men and women in one month are:

Muscle Gain Potential Per MonthMenWomen
Added Muscle0.4 - 2.5lbs0.2 - 1lb

However, this is only reflective of how much muscle you have the potential to gain while bulking, but depending on what kind of bulk you’re doing (lean bulk, standard bulk, dirty bulk) there is also potential for fat gain.

  • If you’re lean bulking, then it’s more likely that the weight you’re gaining is mostly muscle. 
  • If you’re standard bulking, then you’ll likely gain equal parts muscle to fat.
  • If you’re dirty bulking (aggressive bulking), then you’ll gain much more fat mass than fat mass.

It’s also important to note that your bulking results depend on many other factors, including your training regimen, genetics, how often you take rest days, and other lifestyle factors.

As Marc Jacobchick, Doctor of Physical Therapy, says:

“The maximum amount of muscle you can gain in one month differs not only between men and women, but also between each individual. Variables such as training intensity, volume, frequency, genetic makeup, diet, rest, and hormonal levels each have a specific effect on muscle gain.”

Is A 1 Month Bulk Enough?

A one-month bulk is likely not enough time for anyone to see significant results unless you’re dirty bulking, which will lead to both muscle and fat gain. 

The additional fat gain may cause you to become very uncomfortable in your body. But if that’s the case, then you probably shouldn’t be dirty bulking.

I would recommend changing your approach and bulking for longer because the more patient you are with the process, the better you’ll look and feel. 

Is A 2-Month Bulk Enough? 

A 2-month bulk may be long enough to see the results that you’re looking for if you’re doing a standard bulk (eating 200-300 calories above maintenance) and feel that you have filled out your frame the way you were intending.

In 2 months, men would have the potential to gain between 0.8 to 5lbs of muscle, and women would have the potential to gain between 0.4 to 2lbs of muscle.

Along with this, there would be some fat mass added but not as much as there would be with a more aggressive bulk.

Those who are lean bulking probably wouldn’t see a significant change after 2 months and would probably need to continue bulking to see the results they’re looking for.

Is A 12-Week Bulk Enough?

A 12-week bulk would be too long for a dirty bulk (gaining mass as fast as possible), it would be an ideal timeframe for a standard bulk (gaining equal parts of fat and muscle), but it may or may not be enough time for those who are lean bulking (gaining a significant amount of muscle with little to no fat).

If you’re dirty bulking, then you would gain way too much fat mass if you were to bulk for 12 weeks.

If you’re doing a standard bulk, then 12 weeks would be within the appropriate time frame to see the best bulking results because you would have the potential to gain .2 to 7.5lbs of muscle and women have the potential to gain 0.6 to 3lbs of muscle with moderate fat gain.

If you’re lean bulking you may be satisfied with your results after 12 weeks or you may want to continue to try and gain more muscle mass because lean bulking is a slower process.

What Should You Do When You Want To Stop Bulking?

When you’re ready to stop bulking you should return to a maintenance level of calories and focus on maintaining your weight even if your goal is to eventually start cutting to shed any additional fat mass that you may have put on.

The main thing to note is that if you were successful in increasing your muscle mass then your maintenance calories may have increased because the more muscle you have the more calories your body will burn, even while at rest.

You can use our calorie calculator to determine your new maintenance calories after your bulk.

This will give you a starting point to work from, but to truly determine your maintenance calories you’ll have to adhere to this intake for a week to see how your body weight and body composition change.

If after a week your body weight stays relatively the same, then we can say that you’re eating at maintenance.

Eating at maintenance for at least 2 weeks will give your body a chance to regulate itself following a bulk. 

After 2 weeks you can determine what your next goal will be and begin pursuing it. You could decide to cut, you could decide to maintain, or you could decide to bulk again.

If you were to dive into a cutting cycle right away following a bulk without finding your new maintenance calories (they won’t be the same as before because you should have increased your muscle mass), then you may decrease your calories more than you need to lose fat.

If your goal is to continue bulking, then you still take the 2-week break at maintenance to stop gaining fat and to give the body a chance to distribute the fat that you did gain to other parts of your body instead of just one area.

When you gain fat quickly, your body doesn’t have a chance to distribute it evenly so it may have just deposited all the fat that you’ve gained in your midsection.

Additionally, a 2-week break from bulking will give your body time to adjust to being at maintenance so that when you do start bulking again, your body will be more responsive to it because it will be a novel stimulus again.

Bulking vs Cutting Cycles: Are They The Same Length?

Bulking and cutting cycles are generally the same length because the timeframe they use is essentially identical but with opposing results.

A conservative cut and a conservative bulk take 12+ weeks, a moderate cut and bulk take 8 to 12 weeks, and an aggressive cut and bulk take 4 to 6 weeks.

  • If your goal is to stay leaner when you’re bulking then it can take 12+ weeks, and if your goal is to get lean but maintain muscle mass while cutting, then it can take 12+ weeks. This would be a conservative approach to bulking and cutting.
  • If your goal is to put on mass quickly and you’re not worried about gaining some fat, then it can take around 8 to 12 weeks of bulking; if your goal is to cut and you’re not worried about losing some muscle, then it can take 8 to 12 weeks. This would be a moderate approach to bulking and cutting.
  • If your goal is to gain weight as fast as possible, then you could bulk in 4 to 6 weeks; if your goal is to lose fat as fast as possible and you’re comfortable with losing muscle mass, then you could cut in 4 to 6 weeks. This would be an aggressive approach to bulking and cutting.

Frequently Asked Questions

How Long Should You Bulk For The First Time?

Those who are bulking for the first time should bulk for 8-12 weeks. If you are new to lifting weights and bulking, this is a sufficient amount of time to gain muscle mass because you can see progress more quickly than someone who’s more advanced.

How Long Should You Bulk Before Cutting?

You shouldn’t bulk for longer than 6 weeks before cutting if doing a dirty bulk because you can gain a lot of fat. If lean bulking, you should bulk for 12-16 weeks before cutting because this is an adequate amount of time to see results.

It’s also important to eat at maintenance for at least 2 weeks before cutting.

However, you can lean bulk for longer than 16 weeks before starting a cut if you’re still not happy with the amount of muscle mass you have.

How Long Is Too Long of A Bulk?

How long is too long too bulk depends on the type of bulk you do and how happy you are with your progress. For a dirty bulk, more than 6 weeks is too long because you have a higher chance of gaining excess fat.

But for a lean bulk, even 16 weeks may not be long enough because you’ll gain muscle more slowly.

What To Read Next

If you’re ready to start bulking, then you should read this article first:

If you’re transitioning from a cut to a bulk, then you’ll want to reverse diet before bulking so you need to read this:

If you’re considering a cut after your bulk, read these article:


Van Anders, S. M., Steiger, J., & Goldey, K. L. (2015). Effects of gendered behavior on testosterone in women and men. Proceedings of the National Academy of Sciences of the United States of America, 112(45), 13805-13810.

About The Author

Amanda Parker

Amanda Parker is an author, nutrition coach, and Certified Naturopath.  She works with bodybuilders, Olympic weightlifters, and powerlifters to increase performance through nutrition and lifestyle coaching.

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