Pores don't stretch and shrink day to day: what changes is how visible they look, driven mostly by oil sitting in the opening and how firm the skin around it is. You can't shrink the pore itself (genetics sets that baseline), but keeping oil and buildup down and protecting collagen makes them look smaller. The specifics are below.
If this is you
Pores that look bigger around your nose and cheeks, with shine back within a couple of hours of washing your face: that's a T-zone oil pattern more than anything else. It gets more noticeable through the day as oil resurfaces and catches the light, then looks calmer again right after cleansing, before the cycle starts over. That daily swing, worse by afternoon, better right after a wash, is actually a useful clue. It points to oil control doing more for you here than anything else on this list.
Why this happens
A pore is the visible opening of a hair follicle and its oil gland. On its own, that opening is small. It looks bigger when oil, dead skin, and product residue sit inside it and stretch the rim outward, which is why oily areas (the nose, the centre of the cheeks, the forehead) show more visible pores than drier ones: sebaceous glands cluster there, and a clogged opening reads as a bigger one.
Sun exposure and normal aging add a second factor. Dermatologists at Cleveland Clinic explain that UV breaks down the collagen and elastin that hold the skin around each pore taut, so the opening stops snapping back into a tight circle and instead sags into a slightly wider, more oval shape. Genetics sets the baseline size you're working with (some people are simply born with larger pores, most often through the T-zone), and nothing changes that permanently. What you can move is everything layered on top of that baseline: how much is sitting inside the opening, and how firm the surrounding skin is. Both swing day to day, which is why the same pores can look noticeably different within the same week.
What actually helps
Niacinamide has the clearest research behind it for this specific pattern. A 2006 clinical study of topical 2% niacinamide found it lowered facial sebum output over four weeks in one study group, and reduced casual surface oil in a separate six-week trial. Less oil sitting in the opening is exactly the mechanism from the section above, so this one is worth prioritising if shine is your main complaint. It won't touch the genetic baseline, but for the midmorning shine, it's doing real work.
Sun protection matters more here than most people expect, since UV is quietly softening the collagen that keeps pores looking tight. A broad-spectrum SPF 30+ every morning, even under makeup and even on cloudy Australian days, protects whatever ground the rest of your routine gains.
Regular, gentle exfoliation (a mild BHA two to three nights a week, not a daily scrub) keeps the opening itself clearer, since a clogged pore reads as a bigger pore. What actually makes things look worse: picking, squeezing, or scrubbing hard enough to irritate the area, since inflamed skin puffs the rim up on top of whatever's already there.
A simple AM/PM routine
- Morning: gentle cleanse, a niacinamide serum or moisturiser, SPF 30+. A plumping, niacinamide-based moisturiser covers both the oil-control and firmness side of this in one step, so you're not layering on extra product just for pores.
- Evening: cleanse, a BHA exfoliant two to three nights a week, then your usual moisturiser on the other nights. Give a new active two to three weeks before deciding whether it's making a difference.
If you're already using niacinamide and want to add an exfoliating acid without the two cancelling each other out, the niacinamide pairings guide covers how to space them.
Further reading: Niacinamide and Brighter-Looking Skin: How It Works and How to Use It
FAQ
Can pores actually be shrunk permanently?
Not the opening itself: genetics sets that size, and nothing applied topically changes it for good. What you're actually managing is how visible the pore looks, by keeping the opening clear and the surrounding skin firm. That's a real, ongoing difference, just not a permanent resize.
Why do pores look bigger some days than others?
Mostly oil. Sebum builds through the day, resurfaces into the pore opening, and catches light, so pores look more obvious by afternoon and calmer right after a cleanse. Humidity, sweat, and product buildup all add to the same effect.
Does niacinamide really help with pore appearance?
The evidence points that way for the oil side of the problem. A 2006 study of 2% niacinamide measured a real drop in facial sebum output over several weeks, and less oil sitting in the opening is the main thing making pores look bigger day to day.
What do Korean skincare routines do differently for pores?
Less a different mechanism, more consistency: a gentle double cleanse to clear the opening without over-stripping, lightweight hydrating layers so skin doesn't overproduce oil to compensate for dryness, and sunscreen worn daily rather than occasionally. None of it is exotic, it's the same handful of habits, done every day instead of some days.
The short version
Large-looking pores are mostly an oil-and-firmness story, not a fixed flaw. Keep the opening clear with gentle, regular exfoliation, bring oil output down with niacinamide, and protect the collagen around each pore with daily SPF. Genetics still sets the floor, but everything above it is yours to work with.
