The job is to know what one patch costs before a smaller box at the till looks like the bargain. A 24-count hydrocolloid sheet and a 9-count microdart pack can both sit around a few pounds. Split each total by the patches you can wear.
Hydrocolloid is the cheap round disc, roughly 15–40p. It collects fluid from a whitehead, an open spot, or anything already weeping. A microdart is a small patch of dissolving cones for a closed early bump, typically £0.60–£2.50 or more each. If the spot is deep, painful, cystic, or it keeps returning in the same place, skip both and see a GP. A patch sits on the surface. It is not a cure.
The hydrocolloid vs microdart comparison is the format fork. This page is how to split the pack.
Why the box price misleads
A bulk hydrocolloid carton holds more stickers, so the shelf price looks sensible. A small microdart pack shows one number, so it looks dear or oddly cheap.
Price per patch is that number divided by the patches you can peel. Count every disc on a mixed sheet, including the tiny ones. A 9-patch cone pack is nine wears. The figures below are the approximate prices already listed on this site. Check the retailer on the day. A sale can change which box is lower.
What a bulk hydrocolloid disc costs
COSRX Master Patch (Amazon UK) is a 24-patch mixed-size sheet, listed around £5.99. Divide by 24 and you are around 25p a disc. Superdrug is the other named path. If the count on the shelf is not 24, it is a different buy.
Mighty Patch Original is one everyday size, 36 times. Around £10–12 for 36 lands nearer 28–33p a disc. Boots has shown about £8.79 / 36, around 24p. Hero UK and Tesco stock it too. The COSRX vs Mighty Patch guide covers the sizes. Stockists are on where to buy hydrocolloid patches.
Mixed sizes help when your spots are not one diameter. One repeated size helps when that diameter already covers. A 25p disc on a closed bump can stay on all night and still look unused, because there was no surface fluid to collect.
What a small microdart pack costs
Revolution Super Dart (Amazon UK) is 9 patches, listed around £5.51–£9. At about £5.51 for 9 you are near 61p each, the bottom of the £0.60–£2.50+ band. At about £9 for the same 9 you are at £1 a patch. Justmylook has shown the low end. Debenhams has shown about £9. The cones sit on a hydrocolloid dome. The Super Dart explainer covers that shape.
That 9-pack total can look like a COSRX sheet at the till. Each cone still costs more per wear than a 25p disc.
Skin Choice Classic Darts are listed around £10.99, and Holland & Barrett stocks that range. Count the patches on the box before you divide £10.99. ACROPASS Trouble Care is listed around £10.05 for 6, about £1.70 a patch, inside the £0.60–£2.50+ band. Notes are on where to buy microdart patches.
Under-eye ovals are a different format, around £6–£15 or more a wear. Leave that price out of a spot-patch sum.
Match the pence to the spot
A closed early bump has no whitehead, no broken surface, and no leak. One microdart, at 61p to £1 or more, matches that spot. Open one square and leave the rest sealed. The storage guide is how to keep the next cone intact.
An open or weeping whitehead wants the round disc. You are in the 15–40p band because that is the format for surface fluid. A £1 cone on that spot uses the small pack for a job a disc already does. A line such as salicylic on the carton does not add a third price band. Read the shape of the patch first.
If a cheap disc stayed clear after a proper night, the bump was often still closed. The unchanged-bump guide is that morning. A larger count of the same disc will not invent fluid.
A first cupboard holds one of each, as in the first kit guide. Then refill the format you opened: the bulk sheet for whiteheads, the small cone pack for closed bumps, with a cheap disc kept for the night a spot opens. A star or dotted outline is still hydrocolloid when the middle is a plain dressing. The novelty vs plain guide is that check.
Divide the listing in front of you
Note the price today, the patch count, and whether you are holding round discs or cones. Split price by count. Set the answer beside 15–40p for a disc, or £0.60–£2.50+ for a cone.
A hydrocolloid price well outside 15–40p may be an under-eye pack or a different count. A microdart price far above £2.50 a patch needs a recount. Then buy the pack that matches tonight’s spot. Check Amazon UK, Boots, Superdrug, or Holland & Barrett on the day.
Where to buy in the UK
COSRX Master Patch (Amazon UK) is the bulk hydrocolloid half: 24 mixed sizes, often around £5.99, about 25p a disc, with Superdrug as the other named path. Revolution Super Dart (Amazon UK) is the small microdart half: 9 patches, often around £5.51–£9, about 61p to £1 each. Check both on the day. How those Amazon links are tagged is on the disclosure page.
Mighty Patch Original stays the Boots hydrocolloid when you only need discs: around £10–12 / 36, or about £8.79 / 36 at Boots. Skin Choice Classic Darts stay the Holland & Barrett microdart, around £10.99. Count that box before you compare it per patch. The lists are on where to buy hydrocolloid patches and where to buy microdart patches.
Further reads are in all guides. If you are still choosing a format rather than a price per patch, start with hydrocolloid vs microdart.