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) is a prescription-only weekly weight loss injection available in the UK through both NHS specialist services and private online prescribing. The cost varies significantly depending on whether you access it through the NHS or privately. NHS availability remains limited and subject to regional variation, whilst private costs typically range from £129 to £320 per month depending on your dose. Understanding pricing, what's included, and your access options can help you make an informed decision about this 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 vs Private Mounjaro Costs in the UK
NHS access: If prescribed through an NHS tier 3 specialist weight management service, Mounjaro is free at point of use (you pay standard prescription charge of £9.90 per item if eligible). However, NHS availability is extremely limited—most regions have long waiting lists, and not all integrated care boards (ICBs) fund tirzepatide yet. Access requires referral from your GP to a specialist service, and eligibility assessment can take months.
Private access: Through GPhC-registered online pharmacies, Mounjaro costs vary by dose. Starting doses (2.5 mg) typically cost £129–£180 per month, whilst maintenance doses (15 mg) cost £240–£320 per month. Each KwikPen contains 4 weekly injections. Private prescriptions require an online clinical assessment from a UK-licensed prescriber—usually £20–£50—which may be included or charged separately depending on the provider.
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.
Factors Affecting Your Mounjaro Cost
Your total Mounjaro cost depends on several factors: dose level (you start at 2.5 mg and increase gradually, so early costs are lower), treatment duration (treatment is typically long-term, making monthly costs cumulative), provider (private costs vary between pharmacies), and eligibility for NHS prescription charges (free or £9.90 per item if eligible). Using our free BMI calculator above can help confirm whether you meet the threshold for prescription weight loss treatment. Many people find tracking progress with our weight loss calculator helps justify ongoing costs by projecting 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 available on the NHS for free?
Yes, if prescribed through an NHS specialist weight management service, Mounjaro is free (or £9.90 prescription charge if applicable). However, NHS availability is very limited. Most regions have significant waiting lists, and not all ICBs currently fund tirzepatide. You'll need a GP referral to specialist services and must meet eligibility criteria.
How much does Mounjaro cost privately in the UK?
Private Mounjaro costs range from approximately £129–£320 per month depending on your dose. Starting doses cost less (around £129–£180 monthly), whilst maximum doses (15 mg) cost £240–£320 per month. Each KwikPen contains 4 weekly injections. Additional costs may include an online clinical assessment (£20–£50).
Why does Mounjaro cost more at higher doses?
Each KwikPen contains the same 4 weekly injections, but higher concentration doses cost more to manufacture and dispense. You start at 2.5 mg and increase every 4 weeks if tolerated, so your costs increase gradually over several months as you reach your maintenance dose.
Can I use my NHS prescription charge exemption for Mounjaro?
Yes, if Mounjaro is prescribed by the NHS, you pay the standard prescription charge (currently £9.90 per item in England) unless you're exempt due to age, medical condition, or benefits. However, availability through the NHS is very limited and varies by region.
Is Mounjaro cheaper than Wegovy in the UK?
Costs are broadly similar—both typically range from £129–£320 monthly privately depending on dose. Mounjaro and Wegovy have different mechanisms (Mounjaro is dual GIP+GLP-1, Wegovy is GLP-1 only), so pricing reflects different formulations. Compare both the weekly weight loss injection costs and expected outcomes with your prescriber. ```
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.