EN 10025: what the standard delivers and what your order has to add

A grade designation is half an order. EN 10025 is a six-part series in which part 1 governs how the steel is ordered, documented and weighed, and part 2 governs what the grade is; neither of them carries the dimensions, which come from a separate standard for each product form. The yield figure in S355 applies to the thinnest thickness range, not to the piece you receive. Below is what each document covers, what the order has to state and where the common gaps sit.

One series, six parts

Quoting EN 10025 without a part number is the first ambiguity in most enquiries, because the parts cover different steel families and carry different requirements.

Two entries in that column are worth checking against your own specification text. The 2019 editions of parts 4 and 6 without the A1 amendment have been withdrawn, so a drawing note that cites EN 10025-6:2019 on its own is citing a superseded document. And the series has only six parts, despite datasheets that occasionally reference a seventh.

The column also shows something that surprises people the first time they check it: part 1 still carries its 2004 date while every material part was reissued in 2019. A current order for a 2019 grade therefore runs on procedural rules published fifteen years earlier, and both documents are in force.

What changed in 2019, and why most descriptions of this standard are out of date

Almost every supplier page explains the series the same way: part 1 carries the delivery conditions, part 2 carries the grades. That description stopped being true in 2019.

The European foreword to the 2019 edition of part 2 states that the part is now a stand-alone standard for technical delivery conditions, covering sampling, test methods, marking, labelling, packaging and drawings, and that part 1 is used alongside it for applications under the construction products regulation. The same foreword records that clauses 5, 12 and 13 of part 1, that is ordering, complaints and options, are no longer relevant.

Part 2 makes the point from the other direction. Its clause on inspection documents says that unless otherwise agreed, the grades are delivered with CE marking and must satisfy part 1 as well; but it also says that abstaining from CE marking can be agreed at the time of order, and in that case part 1 does not apply at all. A delivery is still fully governed, because part 2 carries the delivery conditions itself.

The practical consequence for a buyer is the opposite of what the old description implies. Part 1 is not the procedural rulebook any more; it is the regulatory layer, and it attaches when the steel goes out as a construction product. For everything else, the document to read is part 2.

Reading S355J2+N

The full designation carries four separate pieces: the product type, the strength figure, the quality symbol and the delivery condition.

• S marks a structural steel.
• 355 is the minimum yield strength in MPa, and this is the detail that catches designers out; see the next section.
• J2 is the quality symbol, which sets the impact energy and the temperature at which it is verified. The symbols JR, J0, J2 and K2 are unpacked in Structural steel S235JR, S275JR and S355J2: which grade for which application.
• +N is the delivery condition, not a property.

A complete purchase description pairs that designation with the dimensional standard for the product form, because the two documents answer different questions and one without the other leaves the supplier guessing.

The yield figure belongs to the thinnest range

This is the single most useful thing on this page for anyone reading a drawing. The number in the grade is the minimum yield strength for the thinnest thickness range covered by the standard. As the product gets thicker, the guaranteed minimum steps down, because the same rolling schedule works the material less through the section.

The standard says so in the clause that defines the designation: the number is the minimum specified yield strength for thickness up to and including 16 mm. Everything above that steps down across nine thickness bands.

Minimum yield strength in MPa. So a 90 mm plate in S355J2 is guaranteed 315 MPa, and a 300 mm plate 265 MPa, a quarter below the number in its own name. A designer who sizes a thick member on the headline figure is working with a value the material was never required to meet.

One footnote in the table has a habit of surprising people: for plate, strip and wide flats of 600 mm and over, the values apply transverse to the rolling direction, while for everything else they apply parallel to it.

The carbon equivalent behaves the same way, stepping up with thickness on its own set of bands, so a thick section also carries a looser CEV ceiling than the headline figure suggests.

Quality symbols carry thickness limits too, and they are not symmetrical: JR, J0, J2 and K2 run to 400 mm on flat products but to 250 mm on long products and everything else, while S460 and S500 exist only as long products, from 3 to 150 mm. S235 and S275 have no K2 quality at all.

And one thing about the quality symbol that rarely reaches the buyer: for JR the impact test is verified only when the order asks for it. For J0, J2 and K2 the test is mandatory, but JR carries its 27 J at +20 °C as a specified property that the mill need not demonstrate on your material unless you invoke the option. If a certificate for S235JR arrives without an impact figure, nothing has gone wrong; the order simply did not ask.

Delivery condition: three options, and the supplier picks if you do not

The suffix after the plus sign describes how the steel left the mill. The 2019 edition recognises three conditions for non-alloy structural steel, not two, which is a change many datasheets have not caught up with.

Two things follow, and together they are the most expensive detail on this page.

First, if the order is silent the manufacturer chooses. For long products and hot rolled strip the choice is between all three; for quarto plate it is between +AR and +N. Fixing the condition is an option you have to invoke in the order.

Second, only products ordered and supplied in the normalized or normalizing rolled condition are guaranteed to still meet the property tables if hot forming is carried out after delivery, and the standard states plainly that +AR and +M products are not suitable for hot forming. So a fabricator who intends to bend hot, and who leaves the condition off the order, can legitimately receive material that must not be heated. That is not a supplier error; it is the standard working as written.

A related point that prevents a different confusion: +M here is a delivery condition of an ordinary S355 from part 2, not the fine grain grade S355M from part 4. Same two letters, different thing. And the standard notes that the specified mechanical properties do not depend on the delivery condition, so the condition changes what you may do to the steel, not what it is certified to reach.

What the standard does not cover: the dimensions

EN 10025-2 tells you what the steel is. It does not tell you how straight, how flat or how close to nominal the piece will be. Those live in a separate standard for each product form, which is why a complete order names two standards.

Two traps sit inside that list.

The first is that for beams and channels, one standard is not enough either. EN 10034 gives tolerances for I and H sections but not their dimensions and masses; those come from EN 10365, which was added to the list only in the 2019 edition. And the parallel flange family and the taper flange family are separate: IPN sections are handled by EN 10024, not by EN 10034.

Worth checking against your own office copy: EN 10365 was reissued in 2026 and the 2017 edition was withdrawn on 15 July 2026. A section table printed from the older edition is no longer the current document, and since EN 10025 cites it undated, the new edition is the one that applies to your order.

The second decides what arrives when nobody says anything. Plate cut from continuously hot rolled strip takes its thickness tolerances from EN 10051, not from EN 10029, unless the order agrees otherwise, and for hot-rolled plate the default is EN 10029 class A. So plate cut from coil and quarto plate of the same nominal thickness can arrive under two different tolerance regimes, both correct. If the tighter regime matters, it belongs in the order as an option, not in the complaint afterwards.

One exclusion is worth naming because it catches people: structural hollow sections and tubes are outside the scope of part 2 entirely, and have their own product standards.

How the sections themselves differ, and which one to choose, is set out in Structural steel sections explained: beams, channels and how to choose, and the flat product side in Steel plate and sheet: hot-rolled, chequer and structural. Hollow sections sit outside this series entirely, under their own product standards, as covered in EN 10219 cold-formed hollow sections: RHS, SHS and CHS explained.

Mass: one density, and it is in the standard

Both parts carry the same clause, word for word, and it settles a question that causes recurring invoice arguments. Nominal mass is determined from the nominal dimensions using a volumetric mass of 7 850 kg/m³. That is a calculation rule, not a measurement, and it is why the theoretical weight on a quotation and the weight on a weighbridge are not expected to be identical.

The sharper point is what is not there. That single sentence is the whole of what EN 10025 says about mass. There is no mass tolerance anywhere in it, no percentage deviation, no rule for weighing a batch, no distinction between theoretical and actual weight.

Nor does the dimensional layer reliably supply one, and this is where an old habit misleads. Part 1 still cites the plate tolerance standard under a title that promises tolerances on dimensions, shape and mass, because that was the 1991 title. The edition in force since 2010 is titled tolerances on dimensions and shape, and the mass tolerances are gone. Since the reference is undated, the current edition applies. Among the standards on the list, only the channel and bulb flat ones still carry mass in their scope.

So a piece can be fully inside its dimensional tolerance and several per cent away from tabulated weight, and for plate there is now no mass tolerance to argue against at all. The arithmetic behind that, form by form, is in Metal weight guide: how to calculate the weight of steel and aluminium.

Heat treatment after delivery

The scope of part 2 says something that fabricators regularly need in writing. The steels are not intended for heat treatment, with the exception of products supplied in the +N condition, which may be hot formed or normalized after delivery. In the same breath the standard adds that stress relief annealing is permitted.

Two hard limits are attached to that permission, and both sit in the same clause of part 2. Stress relieving above 580 °C, or for longer than one hour, can impair the mechanical properties. And for normalized or normalizing rolled flat products the ceiling drops to 560 °C. Beyond either figure, the standard says the minimum properties after treatment have to be agreed at the time of order, which turns an assumption into a negotiation.

Temperature ranges quoted around the trade that sit well above those figures do not come from the standard. There is also a second warning in the neighbouring clause, aimed at the workshop rather than the furnace: incorrect high-temperature processes such as flame straightening or re-rolling can degrade strength, and products in the +N condition are less sensitive to this than the other delivery conditions. One more reason the condition on the order is not a formality.

Which inspection document you are owed

Here the standard is blunt, and it does not say what most buyers assume. Both parts require the manufacturer to obtain from the purchaser which inspection document under EN 10204 is required, and neither sets a default type. Part 2 goes further: the document type is listed among the information the order shall supply, and it stays in the basic specification even when the buyer selects no options at all. In the standard’s own terms, an order that says nothing about EN 10204 is an incomplete order.

A second document in part 1 is often quoted as though it were the commercial rule, and it is not. The annex on evaluation of conformity contains a table linking yield strength and impact test temperature to a document type, and it looks like a neat answer:

The catch is where that table lives and when it bites. The annex is headed evaluation of conformity, the table sits in the clause on testing of samples taken at the factory by the manufacturer, and the standard states that the annex applies where conformity assessment is required for regulatory purposes. The CE annex confirms the reading by listing that factory testing among the manufacturer’s tasks under the assessment system. In other words it binds the mill inside its factory production control, and it is not a schedule of what a distributor owes on a routine order.

Two things the table is often made to say and does not. It never names 3.1 alone; every entry above the first reads 3.1 or 3.2. And it does not put S355 as a family into the higher tier: S355JR and S355J0 fall in the 2.2 row, because their impact test sits at +20 °C and 0 °C. Only J2 and K2, tested at -20 °C, move up. What each document type actually proves is set out in EN 10204 material certificates: 2.1, 2.2, 3.1 and 3.2 explained, and the CE route itself in CE marking and EN 1090 for steel and aluminium structures.

A note in the same clause is worth carrying into fabrication work: application standards, EN 1090-2 among them, can demand particular document types of their own, and they override the comfortable assumption that a mill certificate of any kind will do.

What to put in the order

Six lines remove almost all the back and forth on a structural steel enquiry:

• The product form and size, for example a flat bar 50 by 8 mm or a plate 10 mm thick.
• The dimensional standard for that form, because the grade standard does not carry it.
• The grade with its quality symbol, written in full as S355J2 rather than as S355.
• The delivery condition if it matters to you, that is +AR or +N.
• The governing thickness, where the design leans on the yield figure, so the right band is checked rather than assumed.
• The inspection document under EN 10204, because the standard puts that choice on you.

What ULAMEX supplies

Structural steel in the common grades sits in the Black Steel category, across plate and sheet, open sections, hollow sections and bars. Which grade suits which job, with the trade-offs spelled out, is covered in Structural steel S235JR, S275JR and S355J2: which grade for which application.

ULAMEX is a metals wholesaler, in the business since 1988, that is 38 years. Dispatch across continental Europe typically takes 2-7 working days. A 3.1 inspection certificate is issued by the manufacturer of the material and we pass it on when the order asks for it; our own structural fabrication is certified to EN 1090-1 EXC2 and EN ISO 3834-2, documented on Certificates.

If you have a drawing and are unsure which combination of grade, quality symbol and delivery condition it actually requires, send it through the contact form and we will come back with a reading of the specification and a non-binding quotation.

Frequently asked questions