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
What Does Mounjaro Cost in the UK?
Mounjaro (tirzepatide) is a prescription-only weight loss injection available in the UK through both NHS specialist services and private online prescribing. The cost varies significantly depending on how you access it. On the NHS, there is typically no direct charge once prescribed through a specialist tier 3 or 4 weight management service. However, private prescriptions from UK-licensed online prescribers usually cost between £129 and £320 per month, depending on your dose and the provider. Individual results vary, and costs reflect the ongoing nature of the treatment alongside lifestyle changes.
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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 Pricing in the UK
Private prescription costs for Mounjaro in the UK typically range from £129 to £320 per month, though this varies by provider and dose. Each KwikPen contains four weeks' supply (four injections), so you'll usually pay monthly. Starting doses (2.5 mg) tend to be cheaper than maximum doses (15 mg). Prices may vary between GPhC-registered online pharmacies, so it's worth comparing. Many private providers offer subscription packages that may be slightly cheaper than one-off purchases. A full treatment course typically starts at 2.5 mg for the first four weeks, then escalates gradually over several months—meaning early costs may be lower than maintenance doses. When budgeting, remember that Mounjaro is usually used long-term, often for 12 months or more, so total annual cost is an important consideration.
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 and Private Options
Access through the NHS is free at point of use, but involves referral to a specialist weight management service, which can involve waiting lists of several months or longer depending on your region. Private access is faster and doesn't require NHS referral—you can have a consultation with a UK-licensed prescriber online and receive a prescription if clinically appropriate. To access Mounjaro privately, you'll need an online clinical assessment with a prescriber who'll review your medical history, BMI, and weight-related health conditions. Use our free BMI calculator to check your starting point before your assessment. Both routes require a genuine clinical need and prescription—Mounjaro is never available without professional assessment, regardless of cost.
- 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 available on the NHS in the UK?
Yes, Mounjaro (tirzepatide) is approved by NICE for NHS use within specialist tier 3 and 4 weight management services. Access is free at point of use, but requires referral from your GP and assessment by a specialist service. Availability and waiting times vary significantly by region and local ICB (Integrated Care Board). Many areas have substantial waiting lists.
How much does Mounjaro cost privately in the UK?
Private Mounjaro costs typically range from £129 to £320 per month through GPhC-registered online pharmacies, depending on your dose. Starting doses (2.5 mg) are usually cheaper than maximum doses (15 mg). Each KwikPen contains four weeks' supply. Compare providers as prices vary. Annual costs can range from approximately £1,500 to £3,800.
What's included in the Mounjaro price?
The price covers the tirzepatide injection itself (KwikPen device with four doses). It doesn't include GP appointments, blood tests, or follow-up consultations with the prescriber, though some private providers include follow-up reviews in their service. You may need separate costs for initial health checks.
Is Mounjaro cheaper than Wegovy in the UK?
Pricing is similar—both range roughly £129–£320 per month privately, depending on dose and provider. Wegovy is typically available at lower starting doses (0.25 mg) so initial costs may be slightly cheaper, but maximum-dose costs are comparable. Direct price comparison depends on your provider and which dose you're prescribed.
Can I get Mounjaro without paying if I'm eligible for NHS treatment?
Yes, if you're referred to an NHS specialist weight management service and assessed as clinically appropriate, Mounjaro is provided free. However, NHS access typically involves waiting lists and regional variation in availability. Your GP can advise whether your local service offers Mounjaro and expected waiting times for your area.
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.