Short answer: any white shirt can, eventually — ours included. Anyone who tells you their shirt is immune to it either hasn't ever worn one before, or isn't being straight with you.
The real question isn't "will it happen." It's "why does it happen, and what do you actually do about it." Worth knowing before you're standing over a sink a few months in, wondering if you've ruined your shirts or if this is just normal.
What actually causes it
Yellowing at the collar and underarms — and that grey ring right where the collar sits on the back of your neck — isn't the fabric failing. It's sweat, sunscreen, deodorant and general body oils building up in the fibres over weeks of wear, especially when a shirt goes from "worn" to "sitting in the wash pile for three days" to "quick cold cycle and hope for the best."
This happens to every white shirt. Cotton poplin does it. Cotton-poly blends do it. Ours does it. It's not a fabric-quality problem — it's a laundry-and-time problem, and two years of daily wear is a long time.
What actually helps
- Wash it sooner rather than later. A shirt that sits sweaty for three days is much harder to bring back than one washed within a day or two.
- Machine wash cold, tumble dry low if you use one. No need to overthink it.
- An occasional oxygen bleach soak. Napisan or any similar oxygen-based bleach — not chlorine — soaked for a few hours every few weeks will lift collar staining that a normal wash cycle won't touch. Same trick that keeps a white school shirt white for a whole term.
- Skip the chlorine bleach. It'll whiten a stain fast, but it also breaks down the stretch fibres over time — so you trade a whiter collar today for a shirt that's lost its stretch in six months. Oxygen bleach doesn't do that.
What the fabric actually does for you
Where our knitted jersey cotton genuinely helps is airflow — it doesn't trap heat and sweat against your skin the way a tightly woven poplin shirt does, so there's less sweat sitting in the fabric to begin with. That's a real difference. It's just not a substitute for actually washing the thing.
Two years is a long test for any garment. Wash it promptly, give it an oxygen bleach soak every few weeks, and it'll hold up. Leave it in the bottom of a bag through a transfer week, and no fabric on earth is coming back from that looking new.
If a shirt ever fails from something other than normal wear — a genuine fault, not eighteen months of daily use — that's what the Mission Guarantee is for. Collar yellowing isn't a fault. It's laundry. Grab the Napisan.