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
Where To Buy Mounjaro In The UK — Cost & Access Explained
If you're looking for the cheapest place to buy Mounjaro in the UK, you have two main routes: NHS specialist services or private online prescription. Costs vary significantly depending on your route, dose, and provider. This guide explains actual pricing, eligibility, and how to access tirzepatide affordably through either pathway, plus what to expect during the clinical assessment process.
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.
Private Mounjaro Costs & What You'll Actually Pay
Private Mounjaro pricing in the UK typically ranges from £129 to £320 per month depending on your dose and the provider. This covers the Mounjaro KwikPen itself plus the online clinical consultation.
- Starting dose (2.5 mg): Usually around £129–£149 per month
- Maintenance doses (5–15 mg): Typically £189–£320 per month as doses increase
- What's included: Prescription, clinical assessment, pharmacy dispensing, and delivery to your home
GPhC-registered online pharmacies handle the prescribing and dispensing. You won't pay separately for the GP consultation — it's bundled into the monthly price. However, prices do vary between providers, so comparing quotes before committing is sensible. Many providers offer repeat prescription discounts or subscription models that can reduce ongoing costs.
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 Access vs Private — Timeline & Availability
NHS route: Free on prescription once approved, but involves referral to tier 3 specialist weight management services, often with waiting lists of 3–12 months depending on your local ICB. NICE has approved tirzepatide for NHS use, but availability and speed vary dramatically by region.
Private route: Available within 48 hours of online assessment, no waiting list, but costs £129–£320 per month. You'll need a UK GP registered address and a valid prescription from a UK-licensed prescriber.
Cost over time: If waiting 6 months for NHS access, the private cost during that wait would be £774–£1,920. Once on NHS, Mounjaro is free, but private remains an option if you prefer faster access or your NHS area hasn't implemented tirzepatide yet. Try our free GLP-1 weight loss calculator to estimate potential weight loss and consider your personal timeline needs.
- 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 cheaper on the NHS or through private prescription?
Once approved by the NHS, Mounjaro is free on prescription — far cheaper than private. However, NHS waiting lists can be 3–12 months. Private costs £129–£320/month but is available immediately. If rapid access matters, private may be worthwhile despite upfront cost. Your GP can advise on NHS eligibility and local waiting times.
Can I get Mounjaro cheaper by buying abroad?
Mounjaro purchased from outside the UK carries significant risks: no UK prescription regulation, authenticity concerns, import legality issues, and no recourse if medication is counterfeit. Always use UK-licensed, GPhC-registered pharmacies. The NHS or regulated private prescribers are the only safe options.
Do I need a separate GP consultation fee before getting a private Mounjaro prescription?
No. Private online prescribers include the clinical assessment fee in the monthly prescription cost (typically £129–£320). You're not charged separately for the consultation. The prescriber reviews your health history, confirms eligibility, and issues a prescription — all in one process.
What is the difference between Mounjaro KwikPen and other tirzepatide pens?
Mounjaro KwikPen is the brand name pre-filled pen manufactured by Eli Lilly. Once your prescription ends or you switch providers, you'll always receive the official KwikPen device. Generic tirzepatide pens exist internationally, but UK prescriptions specify the KwikPen, ensuring consistency and safety.
Will my private Mounjaro prescription be recognised by the NHS if I switch?
A private Mounjaro prescription is separate from NHS records. If you later access Mounjaro through the NHS, your treatment will restart as a new NHS episode. Inform your GP that you've been taking Mounjaro privately — they can note this in your records. This helps with continuity of care but doesn't automatically transfer you to NHS provision.
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.