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 in the UK?
Mounjaro (tirzepatide) pricing in the UK varies significantly depending on whether you access it through the NHS or privately. On the NHS, there is no direct patient cost if prescribed through a specialist weight management service, though waiting lists can be lengthy and regional availability varies considerably. Through private online prescribing, Mounjaro typically costs between £129 and £320 per month depending on your dose and the provider. Understanding both routes—including eligibility criteria, timelines, and what's involved in each—helps you make an informed decision about weight management treatment.
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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.
NHS Access: Eligibility and Cost
Mounjaro on the NHS is free at point of care if prescribed by a specialist weight management service, though you won't pay directly as a patient. Access requires referral from your GP to a tier 3 or tier 4 specialist service. To be eligible, you typically need a BMI of 30 or above, or a BMI of 27–29.9 with at least one weight-related health condition such as type 2 diabetes, hypertension, dyslipidaemia, or sleep apnoea. For adults of South Asian, Chinese, Black African, or Black Caribbean heritage, lower BMI thresholds may apply (from BMI 27.5).
Important context: NICE has approved tirzepatide for use within NHS specialist weight management services. However, NHS availability is patchy—some regions have long waiting lists (12–18 months or more), while others have limited or no access. Your local Integrated Care Board (ICB) determines what's available in your area. Check with your GP about what tier 3 services are available locally before pursuing the NHS route.
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.
Private Access: Costs and Process
Private tirzepatide access in the UK is through GPhC-registered online pharmacies, which typically charge £129–£320 per month depending on your dose. A 2.5 mg starting pen (one month) may cost around £129–£150, while higher doses (15 mg) approach £300–£320 monthly. To access privately, you complete an online clinical assessment with a UK-licensed prescriber. If approved, a prescription is issued and dispensed by a regulated pharmacy. This route avoids NHS waiting lists but requires private payment and is not available on the NHS as a prescription drug benefit.
Private pricing varies by provider and dose titration schedule. Some services offer package pricing for multi-month supplies. Always verify you're using a registered pharmacy—look for the GPhC green cross logo on the website.
- 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 at point of care if prescribed through an NHS specialist weight management service, as there is no direct patient charge. However, access requires GP referral to a tier 3 or 4 service, and availability varies significantly by region. Waiting lists can extend to 12–18 months in some areas, making private access an alternative for those seeking faster treatment.
How much does Mounjaro cost privately in the UK?
Private Mounjaro (tirzepatide) typically costs £129–£320 per month depending on your dose, accessed through online prescribing services and regulated pharmacies. Starting doses (2.5 mg) cost around £129–£150, while the maximum dose (15 mg) may cost £300–£320 monthly. Final price depends on the provider and whether you purchase individual doses or package bundles.
What's the difference between NHS and private Mounjaro access?
NHS access is free at point of care but requires GP referral, specialist assessment, and may involve long waits. Private access is faster (often within days) and avoids waiting lists but requires payment. Both require a prescription from a UK-licensed prescriber following clinical assessment. Individual eligibility and health circumstances determine which route is appropriate for you.
Am I eligible for Mounjaro on the NHS?
You may be eligible if you have a BMI of 30 or above, or 27–29.9 with a weight-related health condition (type 2 diabetes, hypertension, sleep apnoea, or similar). South Asian, Chinese, Black African, or Black Caribbean adults may qualify at lower BMI thresholds. Your GP can assess your eligibility and refer you to a specialist weight management service if appropriate.
How long does it take to get Mounjaro on the NHS versus privately?
NHS access typically takes weeks to months for initial referral and assessment, then may involve further waiting for treatment to begin—totalling 3–18 months depending on your region. Private access is usually faster: clinical assessment can be completed online within 24–48 hours, with your prescription and first dose dispatched shortly after. Timelines vary by provider and current demand.
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.