The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
Free tracker included with every download this week
How Much Does Mounjaro Cost Per Month in the UK?
Mounjaro (tirzepatide) is a prescription-only weight management injection available in the UK through both NHS specialist services and private prescription routes. The cost varies significantly depending on how you access it — whether through the NHS, a private online prescriber, or a specialist weight management clinic. This guide explains the current pricing, what affects the cost, and how the two main access routes work.
10,000+ calculations today · NHS-aligned thresholds · 100% free
Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
Private Mounjaro Costs in the UK
Private prescription costs typically range from £129 to £320 per month, depending on your dose and the provider. Mounjaro is supplied as a KwikPen containing four pre-filled injection pens — enough for four weeks of treatment.
- Lower doses (2.5–5 mg): Usually £129–£180 per month
- Mid-range doses (7.5–10 mg): Usually £180–£240 per month
- Higher doses (12.5–15 mg): Usually £240–£320 per month
Costs reflect the dose strength you're prescribed. Many private providers offer subscription models where you pay monthly for ongoing supply. Some patients find costs reduce after initial titration phases as doses stabilise. Always confirm the exact price for your specific dose before starting treatment, as pricing varies between GPhC-registered pharmacies and online prescribing services.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS Access vs Private Prescription Routes
NHS access is free at the point of use if you're prescribed Mounjaro through a tier 3 specialist weight management service. However, NHS availability is inconsistent — not all regions commission tirzepatide (Mounjaro), and waiting lists can be substantial.
Private prescription routes are typically faster but require payment. You'll complete an online consultation with a UK-licensed prescriber, who assesses your eligibility based on your BMI, health history, and any weight-related conditions. If approved, your prescription is dispensed by a GPhC-registered pharmacy. Use our free BMI calculator above to check whether you might meet typical eligibility criteria (BMI 30 or above, or 27–29.9 with weight-related health conditions). The GLP-1 weight loss calculator can also help you estimate potential outcomes at different doses.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Is Mounjaro free on the NHS in the UK?
Mounjaro is free when prescribed through NHS tier 3 specialist weight management services, but access is limited and varies by region. Not all areas commission the drug, and waiting lists are often long. Your GP can refer you to check availability in your area, though private prescription is typically faster.
What's included in the monthly Mounjaro cost?
The monthly cost covers one KwikPen box containing four pre-filled pens (four weeks of injections). It does not include GP consultations or follow-up appointments, though private prescribing services often bundle these. Check with your provider about what's included before purchasing.
Do you need repeat prescriptions every month?
Yes. Mounjaro is a prescription-only medicine, so you'll need an active prescription each month to obtain new KwikPens. Private providers typically manage this through subscription services, renewing prescriptions automatically if you remain eligible.
Is Mounjaro cheaper than Wegovy in the UK?
Pricing is similar, though they vary by provider and dose. Mounjaro starts at 2.5 mg and goes up to 15 mg, while Wegovy starts lower (0.25 mg) but tops out at 2.4 mg. Both are prescription-only; compare quotes from different providers for accurate pricing in your situation.
Can you switch from Mounjaro to Wegovy to save money?
Switching between medications should only be done under a prescriber's guidance — it's a clinical decision, not a cost-saving decision. Your prescriber will assess which medication is more appropriate for your health profile. Switching involves a transition period and different titration schedules.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.