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 on the NHS?
Mounjaro (tirzepatide) is available on the NHS through specialist weight management services, but availability and cost depend on your local area and eligibility. Unlike standard GP prescriptions, Mounjaro is commissioned through tier 3 specialist services, meaning access varies significantly across the UK. If you're considering Mounjaro, understanding both NHS and private routes will help you explore your options. Use our free GLP-1 weight loss calculator to estimate potential outcomes, and our BMI calculator to check your starting point for eligibility assessment.
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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 to Mounjaro and Eligibility Criteria
NHS access to Mounjaro is through tier 3 specialist weight management services, not standard GP prescription. NICE has approved tirzepatide for use within these specialist services, but availability depends on your local Integrated Care Board (ICB) and commissioning decisions.
You may be eligible for NHS Mounjaro if you have:
- A BMI of 30 kg/m² or above, OR
- A BMI of 27–29.9 kg/m² with at least one weight-related health condition (type 2 diabetes, hypertension, dyslipidaemia, sleep apnoea, or cardiovascular disease)
- Lower thresholds apply if you're of South Asian, Chinese, Black African, or Black Caribbean heritage
Access typically begins with a referral from your GP to your local tier 3 service. However, waiting times can be substantial — many areas have waiting lists of several months or longer. Your GP can check what your local NHS trust offers and whether Mounjaro is currently available in your region. The dose titration schedule follows the same progression as private prescriptions: starting at 2.5 mg and increasing weekly over 20 weeks to a maximum of 15 mg.
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 vs Private Routes — Cost and Timeline Differences
On the NHS, there is no direct patient cost for Mounjaro if you meet eligibility criteria and it's available in your area — the cost is covered by the NHS trust. However, the practical barrier is availability: many regions do not currently commission Mounjaro, and those that do often have lengthy waiting lists.
Private route: Available without NHS referral through online prescribing services and GPhC-registered pharmacies. Private Mounjaro typically costs between £129–£320 per month depending on dose, with the 5 mg maintenance dose around £150–£200/month. You'll need a clinical assessment from a UK-licensed prescriber. The private route offers faster access — often within days rather than months — but you pay the full cost privately. Use our free GLP-1 weight loss calculator to explore different doses and projected outcomes, helping you make an informed decision about which route suits your timeline and budget.
- 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?
Yes, Mounjaro is free on the NHS if you meet eligibility criteria and your local tier 3 specialist weight management service commissions it. However, not all regions currently offer it, and waiting times can be several months or longer. Your GP can advise what's available in your area.
How much does Mounjaro cost privately in the UK?
Private Mounjaro typically costs £129–£320 per month depending on your dose. The 5 mg maintenance dose costs around £150–£200/month. You'll need a prescription from a UK-licensed prescriber following an online clinical assessment with a private provider.
What's the difference between NHS and private Mounjaro access?
NHS Mounjaro is free but requires tier 3 specialist referral and has long waiting lists in many areas. Private Mounjaro is available immediately after assessment but costs monthly. Both follow the same dose titration schedule and are the same medication.
How do I get Mounjaro on the NHS?
Ask your GP for a referral to your local tier 3 specialist weight management service. Your GP will assess your eligibility (BMI and health conditions) and refer you if appropriate. From there, the specialist service will manage your assessment and prescription if Mounjaro is available.
Is tirzepatide cheaper than Wegovy in the UK?
Pricing is similar between tirzepatide (Mounjaro) and semaglutide (Wegovy) in private prescribing — typically £150–£250/month at maintenance doses. On the NHS, both are free if available, but neither is universally commissioned across all regions.
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.