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 prescribing routes. The cost varies significantly depending on whether you access it through the NHS or privately. This guide explains UK pricing, NHS eligibility, and what you can expect to pay for this once-weekly weight loss injection through each route.
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.
NHS Access and Eligibility for Mounjaro in the UK
Mounjaro on the NHS is free at the point of use if you are prescribed it through an NHS specialist weight management service (tier 3 or tier 4). However, access is limited and eligibility criteria are strict. You must have a BMI of 30 or above, or BMI of 27–29.9 with weight-related health conditions such as type 2 diabetes, high blood pressure, or sleep apnoea. You'll need a referral from your GP to a specialist weight management service, which varies significantly by region and NHS ICB (Integrated Care Board). Waiting times for NHS specialist services can be several months or longer in many areas.
- NHS prescription = free medication but specialist assessment required
- Lower BMI thresholds apply for South Asian, Chinese, Black African, and Black Caribbean adults (27.5+)
- Regional variation means some areas have better access than others
- NICE has approved tirzepatide for use within NHS weight management services
Once prescribed, your GP can monitor your progress and manage your care alongside the specialist team. Use our free BMI calculator to check if you fall within the eligibility range for weight management support.
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 Mounjaro Pricing and Access in the UK
Private Mounjaro prescribing costs between approximately £129 and £320 per month depending on your dose and the provider. The cost increases with dose: lower doses (2.5–5 mg) are typically cheaper, while higher doses (12.5–15 mg) cost more. Private prescribing offers faster access without NHS waiting lists — you can start within days of a successful online clinical assessment. You don't need a GP referral, though you must declare any existing health conditions and medications. Private providers typically include the prescription and dispensing fee in quoted prices, though some may charge separately.
- Average monthly cost: £130–£320 depending on dose
- No NHS waiting list — access within days
- Requires online clinical assessment with a UK-licensed prescriber
- Budget approximately £1,550–£3,840 per year for ongoing treatment
Our GLP-1 weight loss calculator can help you understand projected outcomes at different doses, supporting your decision-making alongside cost considerations.
- 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 when prescribed through NHS specialist tier 3 weight management services. However, access is limited and requires GP referral, clinical assessment, and meeting strict BMI criteria. Waiting times can be months or longer depending on your region.
What does Mounjaro cost privately in the UK?
Private Mounjaro costs between £129 and £320 per month depending on your dose. Starting doses (2.5–5 mg) are cheaper; maximum dose (15 mg) costs more. Annual costs range from approximately £1,550 to £3,840 depending on your required dose.
How do I access Mounjaro through the NHS?
Ask your GP for a referral to your local NHS tier 3 specialist weight management service. You'll need a BMI of 30+ or 27–29.9 with weight-related health conditions. Assessment and prescription happen through the specialist service, not your GP.
What's the difference between NHS and private Mounjaro?
NHS Mounjaro is free but involves waiting lists and specialist referrals. Private Mounjaro costs £129–£320/month but offers faster access through online prescribing without NHS referral. Either way, it's the same medication requiring the same clinical assessment.
Are there any other costs associated with Mounjaro in the UK?
Through the NHS, Mounjaro is completely free. Privately, the quoted price typically includes prescription and dispensing. Check if your provider includes follow-up consultations or if these are charged separately. Some private services offer dose adjustment support included in the price.
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.