304, 201 or 316: Which Stainless Steel You Are Actually Buying

A stainless handle costs anywhere between four and eleven dollars from Chinese factories that are all photographing the same shape against the same white background. The photographs are not lying. The metal is different, and the difference does not appear until the hardware has been on a building for a year — which is long after the container cleared, the retention was released and the buyer moved on.

There are three grades in ordinary circulation. 304 is the default architectural stainless: roughly 18% chromium, 8% nickel, no deliberate molybdenum. It is what most people mean when they say stainless steel, it is what most specifications intend, and in a normal inland building it does not corrode. 201 is a substitution alloy invented when nickel got expensive — it drops the nickel to around 4% and makes up the austenite with manganese and nitrogen. It is cheaper by a fifth to a third, it polishes to a finish indistinguishable from 304 across a showroom, and it carries noticeably less corrosion resistance. 316 goes the other way, adding 2 to 3% molybdenum specifically to resist chloride attack, which is the failure mode that pits 304 near salt water and in swimming pools.

The practical consequence is narrow and sharp. Inland, in a dry or temperate climate, 201 will very often be fine for the life of the fit-out, which is why it exists and why it is not a scam. Within a few kilometres of the sea, in a coastal hotel, on a pool enclosure, or anywhere the air carries chloride, 201 develops rust freckles in a single season and 304 develops them eventually. That is the specific case where 316 stops being an upgrade and starts being the only correct answer. It is also the case that produces the most warranty arguments in this industry, because the hardware did not fail — it was the wrong grade for the exposure, and nobody wrote the exposure down.

You can narrow it down on a sample without a laboratory, provided you know what the test does and does not prove. Take a magnet to it. Properly annealed 304 is essentially non-magnetic, and a fridge magnet slides off; 201 is usually weakly magnetic and the magnet drags or tugs. This is a useful screen and it is not proof: cold working — the stamping and forming that makes a rose or a plate — induces magnetism in 304 too, so a magnetic edge on a pressed part means nothing on its own. Test the flat, unformed area, compare against a sample you trust, and treat a strong pull as a reason to ask rather than a verdict. If the answer matters commercially, the only thing that settles it is a material certificate or a positive material identification test on the delivered goods, and both are things you are entitled to ask for before you place the order rather than after.

Two more things travel under the same word and are not grades at all. The first is finish: SSS is satin stainless, PSS is polished stainless, and both codes describe the surface treatment, not the alloy underneath. A polished 201 handle and a polished 304 handle carry the same finish code. The second is construction. A great deal of hardware sold as stainless is stainless-clad or stainless-plated over zinc alloy or steel, which behaves like the substrate as soon as the skin is scratched. If a lever is priced far below the others in a comparison, the interesting question is usually not the grade but whether it is solid at all.

We will be direct about our own catalogue, because the audit that prompted this article was of our own data. Of the 165 Canton Hyland records whose material field mentions stainless steel, 21 state a grade explicitly — some as 304, some as 201, several as "304/201" where the model is genuinely offered in both. The remaining records say "stainless steel" and stop. That is a gap in our published data, not a gap in the factory: the grade is known at production and is confirmed on request against a specific model and order quantity. We are filling it in as the records are revised, and in the meantime the honest instruction is to ask, and to get the answer in writing on the proforma rather than in a chat message.

The question to send a supplier is not "is this stainless steel?", because the answer is always yes and it settles nothing. Ask three things in one line: which grade, solid or plated, and will you state it on the invoice. A supplier who answers all three specifically is quoting you a real product. A supplier who answers "high quality stainless" is quoting you a photograph.

One last note on where grade genuinely does not matter. Interior door furniture in a dry building — a bathroom hook in a private house, an indicator on an office door, a hinge in a corridor — is not an environment that distinguishes these alloys within any reasonable service life. Specifying 316 there is money spent on a certificate. The grade conversation is worth having on external doors, coastal and marine projects, pool and spa areas, commercial kitchens and anywhere cleaning is done with chloride-based products. Everywhere else, buy 304 and spend the difference on the lock.