Gastric Bypass Surgery Cost

Gastric bypass surgery shrinks the size of your stomach so that you feel full more quickly. This restricts the amount of food you eat and means you absorb fewer calories.

It is a relatively safe operation that can deliver effective, long-lasting weight loss results. Most patients can expect to lose up to 70% of their excess body weight.

Gastric bypass surgery costs around £11,500 at a private clinic in the UK. Many clinics provide their patients with financial assistance to help to make the procedure more affordable.

What Is A Gastric Bypass?

After gastric bypass surgery

Gastric bypass surgery is one of the most common weight loss surgeries carried out in the UK. It delivers effective, long-lasting weight loss results. Patients who undergo the procedure can expect to lose up to 70% of their excess body weight within just 18 months of the operation, when combined with a healthy diet and regular exercise.

Gastric bypass surgery works by reducing the size of your stomach to create a smaller pouch. This pouch is then connected to your small intestine much further down than normal, bypassing part of your bowels. The surgery essentially shortcuts the normal procession of food from the stomach to the rest of your digestive system. It is an irreversible procedure, making permanent changes to your stomach and small intestine.

When you eat, the food will not enter most of your stomach and part of your small intestine. This restricts the amount of food you can consume as well as reducing the amount of calories you can absorb. Gastric bypass surgery therefore makes you feel full more quickly, meaning you eat less and lose weight.

Gastric Bypass Surgery Types

There are three types of gastric bypass surgery available in the UK:

  • Mini Gastric Bypass: Otherwise know as a Loop Gastric Bypass this was the first use of the procedure using a small loop of bowel for reconstruction. Despite this being a simpler procedure than the two others available it was abandoned as a technique for weight loss due to the risk of enzymes from the Pancreas and Bile entering the oesophagus from the bowel causing inflammation and ulceration in some cases.
  • Roux-en-Y (RGB): The most commonly used technique in Gastric Bypass procedures in the UK the Roux-en-Y entails a small pouch is created in the stomach through banding or stapling limiting it's capacity dramatically. Next, a Y-shaped segment of the small intestine is attached to allow any ingested food to bypass the large part of the lower intestine (duodenum and jejunum).
  • Biliopancreatic Diversion (BPD): A far more complicated operation in which large parts of the stomach are removed and the final part of the smaller intestine is attached to the pouch of the stomach that remains. Essentially this means that the majority of the smaller intestine is bypassed resulting in less absorption of any food ingested.

Am I Eligible?

Gastric bypass surgery is only recommended by medical professionals if you have repeatedly failed to lose weight through a combination of dieting and exercising. Where a switch to a healthier lifestyle hasn’t helped to achieve your weight loss goals, you may be considered for gastric bypass surgery if:

  • Your BMI is higher than 40

  • Your BMI is higher than 35 and you have a medical condition that could be improved if you lost weight, such as diabetes or high blood pressure

You must also prove that you will be committed to making lifestyle changes over the long-term, and have no medical condition that could increase the risk of the surgery. You must also not smoke.

Eligibility criteria can vary slightly between clinics, so you should attend a consultation with a surgeon who will be able to assess if you are a good candidate for the procedure. Bear in mind that when having gastric bypass surgery at a private clinic, you will not need a GP referral.

Gastric Bypass Cost

The cost of gastric bypass surgery varies depending on the clinic you attend and what’s included in the total price. However, you should expect to pay between £7,995 and £15,000 for a private procedure in the UK.

Be aware that gastric bypass surgery is often more expensive than other types of weight loss surgery, such as a gastric band or a gastric balloon. This reflects how much more complex the surgery is to complete. But you shouldn’t let the price put you off. For some people, a gastric bypass is the most suitable option for their personal circumstances and delivers the best results in terms of long-term weight loss.

We have researched the cost of gastric bypass surgery at some of the most trusted weight loss surgery clinics in the UK, to provide you with an overview of the starting price of the procedure:

Starting Price
The Hospital Group
Spire St Anthony’s Hospital
Ramsay Health Care UK
Healthier Weight
The London Clinic

Financing Gastric Bypass Surgery

Not being able to pay for gastric bypass surgery in one lump sum doesn’t mean you have to put your weight loss plans on hold. Many private weight loss clinics understand that providing finance can enable you to afford the procedure. Because of this, they typically offer either in-house finance options, or work with carefully selected partners, to provide you with the financial support you need. This can help you to better manage the cost of gastric bypass surgery without having to wait until your savings have grown.

Finance options often require you to provide an initial deposit to secure the date of your surgery. This can be a fixed sum, or a percentage of the overall cost. Following your surgery, you will then need to make regular, fixed monthly payments until the remainder of your balance has been paid off. This is typically over 12, 24 or 36 months. You will typically be charged interest on these payments however, although some providers do offer interest-free options.

If you’re interested in paying for your gastric bypass surgery on finance, you should book a consultation with a weight loss clinic. They will be able to talk you through the financial support they offer and help you to choose an option that is best for you. Since consultations are often free, this means that you can visit several clinics and compare the difference finance deals available.

To help you get started, we have put together the comparison table below which provides you with key information about the financial assistance provided at some of the UK’s top private weight loss surgery clinics:

The Hospital Group
  • £500 deposit
  • 0% APR for up to 12 months
  • 9.9% APR for over 12 months
Spire St Anthony’s Hospital
  • No in-house finance
  • Recommend Zebra Health Finance
Ramsay Health Care UK
  • No in-house finance
  • Recommend Zebra Health Finance
Healthier Weight
  • £500 deposit
  • 3.9%-20% APR for up to 60 months
The London Clinic
  • No finance options

Suitable for Weight Loss Surgery? Click your age below to find out!

5 Benefits Of Gastric Bypass Surgery

If you’re considering having gastric bypass surgery, there are many benefits that you can take advantage of from the procedure, including:

  • Quick weight loss results, with patients on average losing up to 70% of their excess body weight over 18 months

  • It improves (or even resolves) health conditions that are associated with being overweight, such as type 2 diabetes, high blood pressure and sleep apnoea

  • Gastric bypass surgery is a permanent weight loss procedure meaning you won’t need any further surgery or adjustments to sustain weight loss

  • It helps you to make long-term lifestyle changes, such as exercising regularly and eating smaller portions

  • It can improve your quality of life, such as your self-esteem, mobility and sexual function

The Procedure

The thought of having gastric bypass surgery can be daunting, but with a trustworthy clinic and medical team, there is no need to worry! This procedure is carried out thousands of times every year in the UK, and has a very high success rate.

We have put together a step-by-step guide of gastric bypass surgery to give you an idea of what to expect on the before, during and after your operation.


  • You will need to attend a consultation with a surgeon and dietician. They will assess your health and diet history to determine your suitability for the procedure. You may also need to undergo a psychological assessment by a trained professional.

  • A few weeks before your surgery, you’ll be invited to a pre-operative health check. Here you will need to have some blood tests, ECG (heart trace) and an x-ray.

  • In the run up to your surgery, you must abstain from drinking and smoking, as these behaviours can greatly increase the risk of serious complications such as blood clots and infection.

  • You’ll be put on a healthy eating and exercise plan, in order to ensure you are in the best health possible for your procedure. This will typically be a calorie-controlled diet that is low in fat, carbohydrates and refined sugars.

  • A liquid diet will be introduced two weeks before the operation where both protein shakes and clear liquids are regularly consumed. This will shrink the size of your liver, making it easier to operate on your stomach.

  • On the day of your surgery, you’ll need to fast for six hours before your operation so that there is nothing in the stomach during the surgery.

  • You will be placed into a robe and compression stockings, and will be given a blood-thinning injection to prevent clotting.


  • You will be placed on a surgical bed where you’ll be given a general anaesthetic. This means that you will be asleep throughout your gastric bypass surgery.

  • The operation typically takes between two and three hours to perform, depending on how complex it is.

  • Your surgeon will typically use laparoscopic (keyhole) surgery. They will start by making five to six small holes in your abdomen through which they will insert surgical instruments along with a device called a laparoscope. This is essentially a camera with a light, attached to a long rigid tube that relays footage to a nearby screen to allow the surgeon to see what they are doing.

  • You surgeon will then separate the top part of your stomach from the bottom part, using a stapling device or stitches. This will create a small pouch, dramatically reducing the size of your stomach.

  • This small pouch is then connected to your small intestine, bypassing the rest of your stomach and allowing food to travel from the pouch through the new route to the small intestine.


  • You’ll be transferred to a recovery room on the surgical ward. Here, specially trained nurses will closely monitor your health.

  • Once you are awake, you will be given water to drink along with painkillers to ease any discomfort.

  • You will also be encouraged to get up and move around once you feel able to. This will minimise the risk of blood clots.

  • The holes made in your abdomen during the surgery will be closed using glue, or sometimes stitches to allow them to heal. A dressing may also be applied if there is oozing from your wounds. Because of this, you will not be permitted to have a shower in the first 24 hours after your operation.

  • You may have had a catheter fitted to pass urine into a bag. You will also have a nasogastric tube, which is fitted into the nose and runs down to the stomach to ensure the stomach pouch remains empty. These will all normally be removed in the first couple of days following your surgery.

Suitable for Weight Loss Surgery? Click your age below to find out!

Recovery For Gastric Bypass Surgery

You will be required to stay in hospital for a few days after your gastric bypass surgery for monitoring, before you will be discharged. If you had laparoscopic keyhole surgery, this will usually be 1 to 3 days. If you had open surgery, your hospital stay will likely be longer.

Upon your discharge from hospital, you will be seen by a member of your surgical team who will talk you through the expected recovery from gastric bypass surgery. You will be given detailed instructions both verbally and in writing, which you must follow carefully. You may also be given a contact number in case you encounter any problems once at home.

You will not be able to drive when leaving hospital, so you should arrange for someone to collect you and take you home.

Once home, you need to get plenty of rest. You will be unable to resume your normal activities for at least 3 weeks – this includes returning to work.

In order for your gastric bypass to be effective at helping you to lose weight, you must follow a strict diet. This will be explained to you by your dietician, but will require you to eat 3 balanced meals a day and to avoid snacking.

Following surgery, you will only be able to consume liquid food or drink whilst your stomach recovers from the operation. Over time, this can gradually be built up to pureed and soft foods, before it is safe to consume solid foods again.

Food Type
Length Of Time
Suggested Food
1-7 days
  • Smooth soup
  • Fruit juice
  • Protein shakes
7-14 days
  • Yoghurt
  • Scrambled eggs
  • Smoothies
14-21 days
  • Pasta
  • Fish
  • Well-cooked vegetables
21+ days
  • Rice
  • Fruit

You will also need to introduce light exercise into your everyday routine, such as brisk walking or gentle jogging. This too will help you to sustain weight loss and tone your muscles.

On average, you can expect to lose up to 70% of your excess body fat following gastric bypass surgery. This will only be achieved if you commit to healthy lifestyle changes such as dieting and exercising. Most patients lose the majority of weight within the first 12 months after surgery. By around 18 months, weight loss tends to plateau.

Here Mr Chris Sutton, Consultant Specialist Bariatric Surgeon, outlines how much weight gastric bypass patients can expect to lose as a result of their surgery:


Video Transcript

"With a sleeve gastrectomy average weight loss is about 70% of a patient’s excess weight and that is a similar sort of figure for a gastric bypass, be it a mini gastric bypass or the Roux-en-Y gastric bypass."

Mr Chris Sutton, Consultant Specialist Bariatric Surgeon at Tonic Cosmetic Surgery


Gastric Bypass Risks And Complications

Having gastric bypass surgery puts you at risk of developing a small number of complications. These can occur during the operation, or after whilst you are recovering.

If your surgeon discovers a problem during your operation, the surgery may need to be changed from a keyhole procedure into open surgery. This will increase the time it will take you to recover from gastric bypass surgery.

Following surgery, most patients develop some unpleasant side effects. These tend to only last for a few days however, and can be relieved with over-the-counter medication. Some common side effects that you can expect to experience include:

  • Pain and soreness in the abdomen
  • Nausea and vomiting
  • Swelling and redness around the surgical incisions
  • Indigestion

Be aware that up to 50% of people who have gastric bypass surgery develop a condition known as dumping syndrome. This is characterised by nausea, abdominal pain, diarrhoea and dizziness. It is caused by eating too much sugary or fatty food. To avoid dumping syndrome, you should:

  • Eat low-sugar and low-fat foods
  • Rest for at least 30 minutes after eating
  • Don’t drink during (or immediately after) meals

There are some more serious complications associated with gastric bypass surgery that you should be aware of. If you suffer from a condition associated with your weight, such as high blood pressure or heart disease, you are more at risk of developing a complication. This will be explained to you in full before you undergo the surgery. Complications that can occur from gastric bypass surgery include:

  • Infection at the surgery site or in your chest

  • Internal bleeding from a stomach ulcer

  • Excess or sagging skin in specific areas of the body, such as the stomach and arms

  • Blood clots in the legs or lungs

  • An internal leak from the place at where your intestine is reconnected to your stomach

  • Narrowing or complete blockage of the hole that connects the stomach to the small intestine

  • Vitamin deficiencies that lead to conditions such as anaemia and osteoporosis

To minimise your risk of developing a complication from gastric bypass surgery, we recommend that you follow the guidelines given to you by your surgeon after the operation. Also make sure that you monitor your symptoms carefully and contact your GP or NHS 111 if you start to feel unwell. This is important because some complications do require urgent surgery to be fixed.

Are There Any Alternatives To Gastric Bypass Surgery?

If you are unsure about whether gastric bypass surgery is right for you, there are some alternative methods of weight loss to consider. The first is dieting and exercise. You should try to lose weight through this method before considering surgical weight loss techniques. Attending weight loss support groups in your local area is a good way to help you to commit to making these lifestyle changes.

If you have tried and failed to lose weight through non-surgical methods, there are some alternative surgical options too. A gastric sleeve reduces the size of your stomach by surgically removing a large proportion of it. A gastric band creates a smaller stomach pouch through the use of an adjustable band that is placed around the top part of the stomach, while a gastric balloon involves the oral insertion of a balloon-shaped device into your stomach to make you feel fuller quicker.

If you don’t know which type of weight loss surgery is right for you, book a consultation to meet with a surgeon. By filling out the form at the top of this page, we can put you in touch with trusted surgeons in your area.

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