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 UK Cost Per Month — What You'll Pay
Mounjaro (tirzepatide) costs vary significantly depending on where you access it in the UK. Through private prescribing, monthly costs typically range from £129 to £320, depending on your dose. NHS access is free but involves waiting lists and regional variation. Understanding the cost structure — from starter doses to maximum maintenance — helps you plan ahead. Whether you're comparing Mounjaro with Wegovy or exploring your options, this guide breaks down real UK pricing for 2026.
10,000+ calculations today · NHS-aligned thresholds · 100% free
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.
Mounjaro Pricing by Dose in the UK
Private prescription costs (approximate):
- 2.5 mg dose: £129–£150 per month (starter dose, 4 weeks)
- 5 mg dose: £149–£180 per month (standard maintenance)
- 7.5 mg dose: £170–£210 per month
- 10 mg dose: £190–£240 per month
- 12.5 mg dose: £220–£280 per month
- 15 mg dose: £250–£320 per month (maximum dose)
Each Mounjaro KwikPen contains 4 weeks' worth of injections (four once-weekly pens). Private costs vary by provider and region. NHS access is free through tier 3 specialist weight management services, but availability is extremely limited in many regions with significant waiting lists. Your GP can refer you to your local NHS weight management service if you meet eligibility criteria (BMI 30+ or 27+ with weight-related health conditions).
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.
Mounjaro vs Wegovy — Cost and Clinical Comparison
Wegovy (semaglutide) typically costs £129–£250 per month depending on dose, with similar regional variation. While Mounjaro's maximum dose (15 mg) may cost slightly more than Wegovy's top dose (2.4 mg), both offer comparable monthly pricing ranges. The key difference is mechanism: Mounjaro is a dual GIP and GLP-1 receptor agonist, while Wegovy is a GLP-1 agonist only. SURMOUNT trial data showed Mounjaro produced average weight loss of 15–21% body weight, whilst STEP trial data showed Wegovy around 15% — though individual results vary significantly. Your prescriber will assess which medication suits your health profile and circumstances. Use our GLP-1 weight loss calculator to explore projected 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.
Does the NHS prescribe Mounjaro for weight loss?
Yes, Mounjaro is approved by NICE for NHS use through specialist tier 3 weight management services. However, NHS availability is extremely limited, with significant waiting lists in most regions. Referral comes via your GP, and eligibility is assessed by the specialist service. Private prescription access is faster but involves cost.
How much does a Mounjaro KwikPen cost?
Each KwikPen contains four once-weekly doses (4 weeks' supply). Private costs range from approximately £129–£320 per month depending on dose strength. The starter dose (2.5 mg) costs around £129–£150, whilst the maximum dose (15 mg) can be £250–£320. Always confirm exact pricing with your prescriber or pharmacy.
Is Mounjaro cheaper than Wegovy in the UK?
Costs are broadly comparable. Both range from roughly £129–£250 per month depending on dose. Mounjaro's maximum dose (15 mg) may cost slightly more than Wegovy's top dose (2.4 mg), but this varies by provider. Cost should not be the only comparison — mechanism and suitability matter more.
What affects Mounjaro pricing in the UK?
Pricing varies by dose (starter doses are cheapest), prescribing provider, region, and pharmacy. Private online pharmacies may offer different pricing. Some providers offer payment plans or bulk discounts. Always get a clear quote before starting treatment.
Can I use my NHS prescription privately to save money?
No — NHS and private prescriptions are separate pathways. If you receive an NHS prescription, it's dispensed free through the NHS. If you access private prescription services, you pay the full private cost. You cannot switch between systems mid-treatment without medical guidance.
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.