Bodies By Byrne is supported by its readers. When you purchase through links on our site, we may earn an affiliate commission. Also, as an Amazon affiliate, we earn from qualifying purchases.
How Long Should You Bulk for

How Long Should You Bulk for (When to Stop Bulking)

Bulking is arguably the most difficult dieting/training phase. The process of building muscle is significantly slower than losing body fat when on a cut and the indicators for progress are much more difficult to track. 

While eating more food and training hard seems like the most fun and straightforward thing (which it can be), you’d be surprised by how few people know how to successfully bulk. 

How long should you bulk for? A typical bulking phase should last for 4 – 8 months whilst following a gradual increase in a weekly calorie surplus. For an optimal bulk, you should not bulk after your body fat reaches 15% as fat gain will then start to accumulate faster than muscle tissue. 

The key issue with bulking is usually the timeline. If you consume too large of a calorie surplus and for too long, it’s inevitable that you’ll gain excess and unwanted body fat. There’s also the flip side in that people don’t bulk for long enough and fail to build any new and noticeable muscle tissue. 

Therefore, I’ll cover in this article how long you should bulk for and most importantly, what a realistic timeline should look like. 

What Is the Purpose of a Bulk 

The sole purpose of a bulking phase is to build muscle. A secondary reason can be to build strength, but new muscle tissue and size is the goal for most people that embark on a bulk.

‘Bulking up’ however, is a term that means something different depending on who you ask. In my experience, most people want to bulk up mainly to build muscle mass, fill out their clothes more, and ultimately look better naked. There are some that just want to get bigger in general. These are the people that are not too concerned with adding excess body fat. 

If you fall into the first category, your aim each week should be to build 0.25lbs – 0.5lbs of muscle while also gaining the least amount of body fat. 

This might not seem like much weight initially and the numbers may even surprise you but the natural limit or rate of muscle growth (on average) is around 0.25lbs – 0.5lbs per week. Beginners can usually see quicker results but this then averages out over the duration of a year. 

You also need to consider that while it might not seem like much in the short term, 25lbs of lean muscle mass in a year will transform any physique. This long-term mentality is essential for a bulk, yet most people rush this process and get sub-par or unwanted results. 

How Long Should You Bulk for 

When cutting, the length of time is easier to judge. Most people can comfortably lose 2lbs – 3lbs of body fat per week at a sustainable rate. You also see your physique changing from week to week and 12 – 24 weeks is long enough for most people to get lean and have a successful cut. 

Bulking is the complete opposite. Changes to your weight need to be minimal with 1lb a week being too high and 1lb every two weeks being far more productive. This accounts for muscle growth and additional water retention that comes with an increased carbohydrate intake. 

Note – for every 1g of carbs you consume you will also store 4g of water as a result. This quickly adds up when it comes to the scale weight which is why people see a rapid increase after cheat days or when starting a bulk. 

You’ll also see less noticeable changes to your physique on a weekly basis when bulking. The visual changes (or lack of…) make it incredibly difficult to track progress by eye and this visual feedback alongside the slow changes to scale weight usually forces people to rush a bulk through frustration and impatience. 

The key to a bulking phase is to plan a long-term bulk and accept that progress will be slow, especially if you want optimal results (lean muscle mass alongside minimal fat gain). 

With a patient approach in mind, a bulk should last for a minimum of 24 weeks with 36 – 52 weeks being the recommended average for beginners. A bulk can also last until you reach a level of 15% body fat. 

With the above in mind, knowing when to stop a bulk is more important than pre-planning a set duration of time. 

When to Stop Bulking 

You should stop bulking when you reach a maximum body fat percentage of 15%. After this point, you will gain body fat at a faster rate than lean muscle tissue and will therefore see diminishing returns for your calorie surplus. 

In my opinion (as well as the opinion of other nutritionists and personal trainers), setting a defined end date for a bulk will often lead to mixed results. People gain body fat at different rates and at a certain point, a calorie surplus will mainly be stored as body fat rather than efficiently being used for muscle growth. 

This transition point is around a body fat percentage of 15%. This will vary depending on how you hold body fat but at this point, your insulin sensitivity and nutrient partitioning will mean that your body favors carb utilization and storage towards body fat rather than muscle glycogen. 

This is the main reason why I said earlier that you should start a bulking phase with as low a body fat percentage as possible. You’ll have a better buffer to build muscle efficiently whilst gaining less body fat in the process. If you start from a place with a higher body fat percentage, the duration of your bulk will be significantly shorter. 

Therefore, rather than setting a bulking duration in terms of weeks, it makes more sense to set it in terms of body fat percentage and stop a bulk once you get to a body fat percentage of 15% or more. 

Can You Bulk for Too Long 

There are two main issues with bulking:

  • You rush a bulk and don’t build enough lean muscle mass
  • You bulk for too long and gain too much excess body fat

The statements above make it seem as though you have a very narrow window for which you can successfully bulk in but really, monitoring your calories and body fat percentage will make this a lot easier. 

The reason why people bulk for too long is linked to the body fat percentage limit I mentioned earlier. If you want to efficiently build lean muscle mass, you need to bulk from a low(er) body fat percentage at the start and finish around a certain point (the 15% range). While it’s not an exact science, once you continue to consume a calorie surplus after this point your results diminish and you’re then essentially bulking for too long. 

This is most commonly the approach taken with a dirty bulk. With a dirty bulk, the aim is to consume as many calories as possible each day in order to fuel heavy lifting sessions and build more muscle mass. As we know, the rate of muscle growth is naturally quite limited so with dirty bulks, people put on substantially more body fat as they can’t fully utilize the surplus calories for muscle growth (like they hoped or intended). 

** If you monitor calories and keep the calorie surplus low – moderate (200 – 350 calories) then this will be less of an issue and you can bulk however you want (dirty, clean, lean, iifym). 

Timeline for a Bulk 

A typical bulking phase has a longer timeline than what you might expect. Regardless of whether or not you attempt to dirty bulk, clean bulk, or lean bulk the rate at which you can build muscle is limited as I mentioned earlier. 

A 4 – 12 week phase (something you’ll usually see as a standard recommendation online) is generally not long enough to see maximal progress. For most people, a successful bulk can take anywhere from 6 – 12 months depending on your starting condition. 

Arguably the most important factor to take into consideration before starting a bulk is your current body fat percentage. Your starting point (alongside the size of your daily calorie surplus) will dictate how long a bulk will last and ideally, you’ll start a bulking phase from as low a body fat percentage as possible. 

I mentioned earlier that you can definitely bulk for too long and after a certain point your progress will see diminishing returns and you’ll also gain body fat at a significantly faster rate than you will lean muscle mass. 

The same is true when starting a bulk. The lower your body fat percentage, the more efficiently your body will store and utilize calories and in particular carbs. You’ll be more insulin sensitive, utilize carbs for muscle glycogen and energy and have a more efficient metabolism. 

While it’s not an easy starting point to get to, your bulk should start with a body fat percentage of around 10%. 10% – 12% is ideal but once you go past 12%, the length of time you can efficiently bulk for will decrease. Therefore, in order to have a productive bulking phase your first step is starting from a low body fat percentage. 

A typical bulking timeline could therefore look like the following:

Week 1

  • Measure and make a note of your current weight and body fat percentage (making sure it’s around 10% – 12% for a starting point. 
  • Download Myfitnesspal (not essential but highly recommended)
  • Calculate your maintenance calorie requirements for a bulk
  • Set your macro ratios alongside a 200 – 300 calorie surplus (this surplus is based on your maintenance calorie requirements from the previous step).
  • Track your calories and weight for the first 7 days to ensure there are no drastic changes to your weight. Remember, the aim for weight gain is 0.5lbs per week as a guide. 
  • If your weight average for the week is around the 0 – 1 pound mark, you’ve got a good baseline to work from.
  • Set a baseline for strength and weights used in the gym. You should be aiming for progressive overload on a weekly basis to get stronger on a bulk so you need a good starting position to use as a guide.

Week 2

Week 1 of a bulk is designed to set a baseline. You need to ensure your calorie surplus is not too high when starting as this will accelerate fat gain. Week 2 should therefore see you increase calories slightly and start to nudge scale weight (though this needs to be across the week as an average, ignoring daily changes).

  • Monitor calories and weight to ensure changes are consistent with week 1
  • Start to progress your lifts. This should be relatively easy for the first 6 – 8 weeks and there should be no signs of a plateau unless you’re an experienced lifter. 

Week 3 (& Onwards)

From week 3 onwards your routine should be very straightforward and repetitive. Try to keep a low-calorie surplus (around 200 calories above maintenance) and make adjustments each week by 100 – 200 calorie increases as weight changes stall. 

Your focus in the gym should be on progressive overload and lifting more than you did the previous session. Lifting more doesn’t necessarily mean more weight though. Increasing reps, reducing rest periods, adding sets, utilizing slower negatives, and yes, increasing weight are all indicators you should look to improve. 

Outside of these two things you should also monitor the following:

  • Ensure there are no drastic jumps in weight on a weekly basis, anything over 2lbs is unlikely to be muscle or water weight and therefore needs to reign back. 
  • Keep your calorie surplus consistent but mix up the food choices and macro ratios so that you don’t get bored of the diet. 
  • Look into ways to increase hunger as it can be quite difficult to bulk with a low appetite 
  • Stick to a similar weight training routine, you’ll need this to track increases in strength. 
  • Still include some cardio 2-3 times per week. Not only is this beneficial for nutrient partitioning and minimizing excess fat gain but it’s also necessary for general health (something often neglected when trying to pile on muscle mass). 
  • Lastly and most importantly… track your body fat percentage at least every two weeks. If your body fat percentage is increasing at a fast rate, your bulking timeline is going to be cut short due to diminishing returns.


Bulking phases can be tricky to get right. You want to gain the most muscle mass possible while also gaining the least amount of body fat in the process. Unfortunately, this means you need to take a more cautious and long-term approach. 

A bulking phase should start from a low body fat percentage of 10% – 12% and end when your body fat reaches 15% (as a general guide, some people hold body fat better than others so can push this slightly). Therefore, trying to set a timeline in terms of weeks or months is less efficient for most people and will cause you to consume too high of a calorie surplus and gain too much body fat. 

A patient approach is essential when it comes to bulking and those that see the best progress take a long term that can last anywhere from 6 – 24 months.

If you truly want to see the best results, ^^ this is the best approach to take!

Join The Newsletter

Receive fitness advice and body recomposition tips every Monday to help you lose at least 1lb of fat every week and build 1lb of muscle mass every fortnight