What Does Your BMI Have to Be for Wegovy?

What BMI do you actually need, and does it change depending on your health?

The licensed BMI threshold for Wegovy (semaglutide 2.4 mg) in the UK is 30 or higher. That covers what clinicians classify as obesity. If your BMI sits between 27 and 29.9, you can still qualify, but only if you have at least one weight-related condition alongside it. Conditions that count include type 2 diabetes, prediabetes, hypertension, dyslipidaemia (raised cholesterol or triglycerides) and obstructive sleep apnoea, among others.

Ethnic background also affects the numbers. UK guidance reduces these thresholds by 2.5 kg/m² for people of South Asian, Chinese, Middle Eastern, Black African or African-Caribbean heritage, reflecting different cardiometabolic risk profiles at lower body weights. So a BMI of 27.5 or above could meet the threshold in those cases, or 24.5 with a qualifying condition. If you want to understand what BMI needs to be for Wegovy across all these scenarios, including the ethnic-background adjustments, that page sets it out clearly. The NHS patient information page for semaglutide sets this out clearly if you want the detail.

One practical note: the NHS BMI calculator is a useful first check, but a BMI reading is not a clinical assessment. Prescribers consider contraindications too, a history of pancreatitis, medullary thyroid cancer, multiple endocrine neoplasia type 2, pregnancy, or breastfeeding would each affect whether Wegovy is appropriate regardless of BMI. You can get a sense of where you stand using the NHS BMI calculator before going further.

How overweight do you need to be to get Wegovy on the NHS versus privately?

This is where the gap between NHS and private access becomes clear. The NHS route follows NICE guidance (TA875), which recommends Wegovy only within a specialist weight management service and only for a maximum of two years. NHS eligibility requires a BMI of at least 35 plus one or more weight-related comorbidities, or a BMI of 30–34.9 meeting specialist-referral criteria. The ethnic-background adjustment of 2.5 kg/m² applies here too, so the equivalent thresholds for eligible groups are 32.5 and 27.5–32.4. Waiting lists for specialist services are often long, and not everyone will be referred.

A private prescription follows the licensed thresholds instead: BMI 30-plus, or 27-plus with a qualifying condition, as described above. That means a significant number of people who don't meet NHS criteria (or who don't want to wait) are eligible for a private prescription, subject to a full clinical assessment. Our detailed guide to BMI requirements for Wegovy covers these two routes side by side if you want a cleaner comparison.

For context on what private treatment typically costs, the Wegovy cost page explains what's included in a private prescription price and how to read market pricing accurately. Worth a look before making any decisions.

What else does a prescriber look at beyond your BMI figure?

BMI is where eligibility starts, not where it ends. A prescriber assessing a Wegovy request will also consider your current medicines (oral contraceptives are worth flagging, since GLP-1 medicines can affect how the gut absorbs other drugs) along with any history of gallbladder problems, kidney disease, or mental health conditions. If you take other medicines for blood sugar or blood pressure, those interactions need reviewing too.

For women of reproductive age, contraception is an active consideration. The NHS recommends discussing contraceptive methods with your prescriber before starting, and anyone planning a pregnancy should not use Wegovy. The medicine is not licensed for use in those under 18.

The treatment overview on the Wegovy information page covers the medicine's mechanism, titration schedule and side-effect profile in more detail. And if you're still working out which option suits you (injectable semaglutide, tirzepatide, or the newer oral route) the weight-loss treatment overview sets out the landscape. Our prescribers, profiled on the clinical team page, review every consultation personally; there's no algorithm making that call.

What BMI do you need for Wegovy if you've already been on another GLP-1 medicine?

If you're transferring from another GLP-1 treatment (Ozempic, for instance, which is licensed for type 2 diabetes rather than weight loss) the BMI thresholds stay the same. What changes is the clinical review process. A prescriber will want evidence of your current dose, your treatment history, and ideally a recent weight record before approving Wegovy or adjusting to a higher dose.

The same applies to the newer 7.2 mg Wegovy pen, approved by the MHRA in April 2026. That higher dose is licensed for adults with a BMI of 30 or above only; the lower qualifying threshold of 27 with a comorbidity does not apply to the 7.2 mg pen specifically. If you're considering that route, it's worth raising at your consultation. Pages covering the specific eligibility nuances around the BMI needed for Wegovy and how overweight you need to be to qualify go into that in more depth.

If you'd like a prescriber to review your eligibility properly, start your free consultation and a GPhC-registered independent prescriber will assess your details the same day.