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
Mounjaro Cost Comparison in the UK
If you're considering Mounjaro (tirzepatide) for weight management in the UK, cost is a crucial factor in your decision. The price you pay depends entirely on whether you access the medication through the NHS or a private route — and availability varies significantly by region. This guide explains the real costs, eligibility criteria, and what to expect at each step of the process.
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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: Cost, Eligibility, and Reality
On the NHS, Mounjaro is free at point of use — you only pay standard prescription charges (£9.90 per item in England as of 2024, or nothing if you're exempt). However, NHS access is strictly limited. Mounjaro is available through NICE-approved tier 3 specialist weight management services only, not standard GP prescription. You must be referred by your GP and meet strict eligibility criteria: BMI 30 or above (or 27+ with weight-related health conditions such as type 2 diabetes, high blood pressure, or cardiovascular disease). For South Asian, Chinese, Black African, or Black Caribbean adults, lower BMI thresholds apply. The major challenge: waiting lists for NHS tier 3 services can be months or even years in some regions. Some ICBs (Integrated Care Boards) have suspended new referrals entirely due to demand. Access varies dramatically by postcode — your location determines whether you can access Mounjaro through the NHS at all.
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 Route: Costs, Speed, and What to Budget
Privately, Mounjaro costs significantly more but offers immediate access without waiting lists. You'll pay approximately £150–£250 per month depending on your dose. A starting dose (2.5 mg) costs around £150–£180 per month, while the maximum dose (15 mg) costs £220–£280 per month. Each KwikPen contains 4 weeks' supply and requires a prescription from a UK-licensed prescriber, obtained via an online clinical assessment with a GPhC-registered pharmacy. You must budget for ongoing private costs indefinitely — these medications are not supported after a set period. Some private providers offer slightly lower prices at higher doses, so shopping around is worthwhile. Unlike the NHS, private access is available immediately and doesn't depend on your location or regional funding decisions.
- 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.
How much does Mounjaro cost on the NHS?
Mounjaro is free on the NHS (you pay only standard prescription charges of £9.90 per item in England), but access is through specialist tier 3 weight management services only, not standard GP prescription. Availability is extremely limited and varies significantly by region — many areas have suspended new referrals.
What's the total private cost for a year of Mounjaro?
Private Mounjaro costs approximately £150–£280 per month depending on dose, meaning £1,800–£3,360 per year. Starting doses are cheaper (around £150–£180/month) and maximum doses cost more (£220–£280/month). Budget for ongoing costs, as these medications are typically long-term.
Can I get Mounjaro from my GP on the NHS?
No. Your GP cannot prescribe Mounjaro on the NHS — it's available only through specialist tier 3 weight management services via referral. This typically involves a waiting list and assessment by a multidisciplinary team. Availability depends on your region.
How do I access Mounjaro privately in the UK?
Complete an online clinical assessment with a GPhC-registered pharmacy. A UK-licensed prescriber reviews your health information and issues a prescription if appropriate. The pharmacy then dispenses your Mounjaro KwikPen. The entire process typically takes 24–48 hours from assessment to delivery.
Is Mounjaro cheaper than Wegovy on private prescription?
Costs are comparable — both typically range £150–£280 per month privately depending on dose. Mounjaro and Wegovy (semaglutide) have similar private pricing in the UK. Your GP or prescriber can advise which option is appropriate for your individual health profile.
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.