The job on the high street is not to find a cleverer hydrocolloid. COSRX Master Patch and Mighty Patch Original are the same format: a thin sticky disc that absorbs fluid from a whitehead, an open spot, or anything already weeping. What changes is the pack — how many discs, whether the sizes mix, which shop stocks it, and roughly what each disc costs once you divide the box.
If the bump is closed and still under the skin, neither pack is the bargain. That is a microdart job, typically £0.60–£2.50+ a cone. If it is deep, painful, cystic, or it keeps returning, skip both formats and see a GP. The hydrocolloid vs microdart comparison is the 60-second fork; this page is for people who already need the cheap round dressing.
What you actually get
COSRX Master Patch (Amazon UK) is a 24-patch mixed-size sheet. You peel different diameters off the same film: small dots for a tight crease, larger discs when the spot needs a rim of clean skin around it. It is one of the most widely stocked hydrocolloid packs in the UK, and the site’s listed price is often around £5.99 — check the retailer on the day.
Mighty Patch Original (Amazon UK) is Hero’s everyday hydrocolloid dot in a 36-pack. One size, repeated. You are not sorting a sheet; you are taking the same disc thirty-six times. The site’s listed band is around £10–12 for that 36-pack. Boots has shown about £8.79 / 36. Hero UK and Tesco also list it. Prices move; treat those figures as a snapshot, not a promise.
Both are plain hydrocolloid. You are comparing two ways to buy the cheap format, not two different jobs.
Roughly what a disc costs
Everyday hydrocolloid sits in a wide pence band — roughly 15–40p a patch on this site — because pack prices jump around. Inside that band, the two packs are closer than the box totals suggest.
Divide COSRX’s often-listed £5.99 by 24 and you are around 25p a disc. Mighty Patch at the listed £10–12 / 36 lands nearer 28–33p. At the Boots figure of about £8.79 / 36 you are back around 24p — the same neighbourhood as COSRX, with twelve extra discs in the box.
That is why “which pack is cheaper” is the wrong first question. The 24-pack looks smaller at the till; the 36-pack looks dearer until you count the discs. Check the retailer, then divide — a dip on Amazon or a higher Boots ticket can flip the ranking in a week. A 25p disc that stays clear overnight was still the wrong format.
Mixed sizes versus one everyday dot
The practical difference is the sheet, not the glue.
COSRX’s mixed sheet is useful if your spots are not one diameter. A chin crease wants a small disc; a cheek whitehead wants a rim. Too small and the edge sits on the fluid. Too large and you fight a crease you did not need. If you already skip the tiny dots, the 24-count is an 18-count in disguise.
Mighty Patch Original is simpler: one everyday size, 36 times. Fine if that diameter already covers with a small rim. Annoying if you fold a disc to sit beside the nose, or leave a gap around a larger open spot. You cannot mix sizes inside that Original pack.
Overnight hold is not a brand property. Dry skin, no moisturiser under the disc, and a size that actually covers matter more than the carton. For the stick-it-on steps, use the overnight apply guide.
Where they sit on a UK shop floor
COSRX is the Superdrug-and-Amazon pattern on this site. Mighty Patch is the wider grocery and high-street pattern: Hero’s own UK shop, Tesco, Boots, and Amazon UK. Full stockist notes live on where to buy hydrocolloid patches.
Value includes whether you will actually buy it. A disc in the weekly shop can beat a similar pence count that needs a separate Superdrug trip; an Amazon box that arrives after the spot has gone is not a saving. If you only buy at Boots, Mighty Patch Original is already there. If you already order COSRX on Amazon UK, you do not need a second brand for the same job.
Which pack to buy
Buy COSRX Master Patch when you want mixed diameters in one sheet and the till price is still around £5.99 — or better. Reach for it if your spots are not one size.
Buy Mighty Patch Original when you want more of one everyday disc on the Boots / Hero UK / Tesco path, and the 36-count still divides inside that 15–40p band. Reach for it if the mixed sheet leaves leftover tiny dots you never use.
Buy neither as a “better hydrocolloid”. They absorb fluid the same way. If one pack peels off, look at dry skin and size before you switch brand. If the disc stays on and stays clear, switch format, not logo. An under-eye dissolving pair is a different format, at pounds per wear rather than pence.
Where to buy in the UK
Hydrocolloid is the cheap format: roughly 15–40p a patch, though pack prices move. COSRX Master Patch (Amazon UK) is the 24-patch mixed-size sheet, often listed around £5.99 — Superdrug is the other named path; check the retailer on the day. Mighty Patch Original (Amazon UK) is the 36-pack of one everyday size, typically listed around £10–12, with Boots often nearer £8.79 / 36, plus Hero UK and Tesco. The stockist list is on where to buy hydrocolloid patches.
More pack notes sit in all guides. If you are still choosing a format rather than a 24-count versus a 36-count, start with hydrocolloid vs microdart.