Mounjaro 12.5mg Price UK: The Maintenance-Dose Comparison

Looking for the Mounjaro 12.5mg price in the UK? You've reached one of the higher maintenance doses, which means the number that matters now isn't a first-month promo — it's what you'll pay, month after month, for the pen you may stay on long-term. We've done the maths across every regulated provider we track, using live figures last checked on 24 August 2026. No invented prices, no pay-to-play ordering.

The 12.5 mg dose sits one step below the 15 mg maximum. It's a genuine treatment strength (unlike the 2.5 mg starter pen), so if you've titrated up to it, you're likely paying this every four weeks for a while. That makes the price gap between providers a real, recurring cost — not a one-off.

Mounjaro 12.5mg price UK: the cheapest providers ranked

Here are ten of the cheapest providers for the 12.5 mg pen, sorted by ongoing price for four weekly doses. First-month promotions almost always apply to the 2.5 mg starter pen only, so they don't help you here — this is the list price you'll actually pay at this dose.

Prices last checked 01 September 2026. All providers listed are GPhC-registered pharmacies or CQC-regulated clinics; this is price information, not an offer of supply. Confirm the current price on the provider's own site before ordering.

The cheapest end of the table clusters tightly — everything from Next Script to Dr Weightmans sits within about £9. The bigger story is the full range: across every provider we track, the 12.5 mg pen runs from £246 to £344. That's a £98 monthly gap for a medicine that is chemically identical whoever dispenses it. Over six months at this dose, choosing the wrong provider could cost you nearly £600 more. We explain the drivers in why Mounjaro prices vary by £80+ for the same pen.

Why the 12.5mg price matters more than the starter deal

When you first started Mounjaro, you probably chose a provider on the strength of a first-month offer — £122 at Chemist4U, £125 at The Weight Clinic, and so on. Those promos only ever applied to the 2.5 mg starter pen. By the time you reach 12.5 mg, the discount is long gone and you're paying the standard rate.

This is exactly where a lot of people overpay. A provider with a loud opening deal can quietly charge £330+ at the higher doses. If you've been on your starting pharmacy for a few months and never re-checked, it's worth comparing again now — switching provider between doses is straightforward, since each new dose needs a fresh prescription review anyway.

If you're weighing up whether to move, our guide on Mounjaro subscription vs one-off shows how billing structure affects the real cost, and Mounjaro first-month offers explains which opening deals genuinely translate into long-term value.

How 12.5mg fits into the dosing ladder

Mounjaro is titrated slowly to reduce side effects. You start at 2.5 mg weekly for four weeks (a starter dose, not a treatment dose), then move to 5 mg, and step up in 2.5 mg increments — 7.5, 10, 12.5 — after at least four weeks at each level, up to a maximum of 15 mg. Your maintenance dose is tailored to you, so not everyone reaches 12.5 mg; some people settle at 5 or 10 mg.

In the SURMOUNT-1 trial, average weight loss was around 21.4% at 10 mg and 22.5% at 15 mg over 72 weeks, so 12.5 mg sits between these as a strong maintenance strength. Whether you go higher is a decision for your prescriber, based on how you're responding and tolerating the medicine — not on price.

12.5mg vs the doses either side

It's useful to see where 12.5 mg sits relative to 10 mg and 15 mg, because most providers space these fairly evenly. At the cheapest end, stepping from 10 mg to 12.5 mg typically adds £15–£20 a month, and 12.5 mg to 15 mg another £15–£20. A few providers, though, jump much more steeply between doses, so check the whole ladder before committing.

For the doses below this one, see our Mounjaro 7.5mg price comparison and Mounjaro 2.5mg price comparison. If you just want the outright cheapest route from day one, our cheapest Mounjaro UK ranking pulls it all together. And you can always check the live homepage price table for every dose and provider in one place.

A quick word on side effects

The most common side effects at any Mounjaro dose are nausea, diarrhoea, constipation, vomiting and tiredness. Rarer but serious risks include pancreatitis, gallstones and dehydration that can strain the kidneys. If you experience a side effect, you can report it through the MHRA Yellow Card scheme. Mounjaro is a prescription-only medicine and a prescriber decides whether it's suitable for you — this article is price and information only, not medical advice.

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