How much do you have to weigh to get Mounjaro?

Where the BMI thresholds come from, and why a number alone isn't the full picture

The licensed thresholds for tirzepatide (the medicine sold as Mounjaro) were established through the SURMOUNT clinical programme and then reviewed by the MHRA and NICE before the medicine reached UK patients. NICE's appraisal of tirzepatide (TA1026), published in December 2024, recommends it for adults with a BMI of at least 35 who also have a weight-related comorbidity, for NHS access specifically. The private licensed criteria follow the Summary of Product Characteristics directly: BMI 30 or above, or BMI 27 or above alongside a qualifying condition.

That qualifying condition can be a number of things: prediabetes, established type 2 diabetes, hypertension, dyslipidaemia, obstructive sleep apnoea, or osteoarthritis are the most commonly cited. So if your BMI sits at 28.5 and your GP has flagged raised blood pressure, you may well meet the threshold. If your BMI is 31 with no other conditions, you likely meet it on BMI alone. The prescriber looks at the whole clinical picture, current medications, medical history, and whether there are any reasons the medicine would not be suitable.

One thing worth letting go of: the idea that Mounjaro is only for people who are very far above a healthy weight. The 27-plus threshold with a comorbidity was set precisely because excess weight compounds other health conditions even at lower BMIs. The evidence supports treatment earlier, not only as a last resort.

For a thorough walkthrough of how height and weight translate to BMI eligibility, our Mounjaro weight eligibility guide includes real worked examples.

What Mounjaro costs privately in the UK, and what any honest answer includes

Once you know you meet the weight and health criteria, the next question is usually about price. UK private weight-loss treatment is priced per pen, per month, and varies by dose and provider. Since Eli Lilly raised its UK list price in September 2025, the highest-dose pen's list price rose from roughly £122 to roughly £330 for a four-week supply, and reported private prices across the market have ranged from approximately £149 to £375 per month depending on dose and clinic. Those are widely reported market figures, hedged as such, individual providers set their own prices.

What those headline figures sometimes don't include is worth knowing before you compare. Some providers charge separately for the consultation, the prescription, delivery, and any follow-up clinical support. A price that looks competitive at first glance can reach a different total once those are added. Our Mounjaro price page covers what a complete, clinically supervised cost looks like versus a stripped-back advertised rate.

At nume, one price covers the consultation, the prescription, the treatment, and free next-working-day delivery, plus access to our prescribers for aftercare. We are not the cheapest option on the market, deliberately. What you are paying for is a clinical service that holds itself to the same standards as a high-street pharmacy, not a fulfilment operation. Current treatment pricing is shown on our treatment page, alongside how the consultation works.

Why the 'cheapest Mounjaro' question points in the wrong direction

For most purchases, price is a perfectly sensible filter. For a prescription medicine with a licensed eligibility threshold, it isn't. The NHS medicines page for tirzepatide makes clear that this is a Prescription-Only Medicine requiring clinical assessment, it cannot legally be supplied without one. Sellers offering it at prices far below the market, with no clinical assessment, are a red flag. The MHRA has warned publicly and repeatedly about fake weight-loss pens sold online; some counterfeit pens have contained insulin rather than the labelled medicine.

The practical consequence is that the pricing question for Mounjaro is better framed as: does this price include everything a safe, legal supply requires? That means a real consultation with a registered prescriber, identity and weight verification, a legitimate UK-licensed supply chain, and clinical review before every repeat order. If any of those are absent, the lower price comes with a risk the number doesn't reflect.

None of this means private treatment has to be opaque. You can verify any online pharmacy on the GPhC pharmacy register in under a minute. Our GPhC premises registration is 9012878, checkable directly on that register. If you're thinking about how much weight you might lose once treatment starts, our Mounjaro weight loss results guide summarises the clinical trial evidence honestly, including what the SURMOUNT-1 data actually showed and what drives variation between individuals. And if appetite changes during treatment have you wondering about eating habits, our guide to eating on Mounjaro covers what patients commonly notice.

A prescriber who has reviewed your health information is the right person to confirm your eligibility, recommend a starting dose, and make sure the treatment fits around your other medicines, and our guide to how much Mounjaro you inject explains how dosing works from the first pen onwards. That conversation costs nothing at nume, and it happens the same day you apply. If you haven't started treatment yet, it's also worth checking whether you qualify for our Mounjaro new customer discount, which reduces the cost of your first order.