304 Stainless Steel Equivalent EN Material: 1.4301 Explained
The closest EN comparison for Type 304 is grade 1.4301, named X5CrNi18-10. It also aligns with UNS S30400 and is commonly compared with SUS304—but a comparison is not automatic approval to substitute one standard for another.
Photo: Ramesh Ramaiah / Wikimedia Commons, CC BY-SA 3.0.
What is the EN equivalent of 304 stainless steel?
For general cross-referencing, use EN 1.4301 / X5CrNi18-10 as the European comparison to Type 304 / UNS S30400. Both describe a general-purpose, chromium-nickel austenitic stainless steel with overlapping chemistry and similar fabrication behavior.
The word equivalent needs care. Product form, thickness, delivery condition, mechanical-property test method, surface finish and inspection document still belong to the governing standard. BSSA explicitly warns that international grade tables are comparisons and should not replace the individual standards.
304, 1.4301, X5CrNi18-10 and S30400 identify the same alloy family
The identifiers come from different designation systems. The table is useful for communication, but the purchase order must still name the specification that controls acceptance.
| System | Common designation | Region / use | What it controls |
|---|---|---|---|
| AISI / common type | 304 | Common worldwide shorthand | Alloy family name; not a complete procurement specification by itself |
| UNS | S30400 | North American unified numbering | Composition identity used by ASTM and other specifications |
| EN steel number | 1.4301 | Europe | Unique material number in the EN stainless-steel system |
| EN steel name | X5CrNi18-10 | Europe | Composition-based grade name paired with 1.4301 |
| JIS comparison | SUS304 | Japan | Japanese grade used with the applicable JIS product standard |
| Legacy German reference | Werkstoff 1.4301 / V2A | Germany | Legacy or trade terminology; use the current EN designation on new drawings |
Do not approve a material solely because the row says “304.” Compare the governing product standards, heat chemistry, mechanical requirements, dimensions, finish and certificate before accepting a cross-border substitution.
What does X5CrNi18-10 mean?
X indicates a high-alloy steel. The number 5 represents a nominal carbon level of roughly 0.05% in the naming convention. CrNi identifies chromium and nickel as the principal alloying elements, while 18-10 expresses their approximate nominal contents.
The steel number 1.4301 is the unique lookup identifier. The name and number should agree on the mill certificate and purchase documentation.
Make the callout readable and auditable
Writing both the name and number reduces ambiguity for engineers, buyers and inspectors. Add the correct EN product standard: EN 10088-2 for flat products, EN 10088-3 for bars, rods, wire, sections and related long products, or the appropriate tube standard for tubing.
PRODUCT STANDARD: EN 10088-2
FINISH: 2B
INSPECTION DOCUMENT: EN 10204 3.1
How close are ASTM Type 304 and EN 1.4301?
The ranges overlap strongly, but the limits are not identical. The most visible differences are the maximum carbon, silicon and sulfur limits. The values below are a practical comparison; the current purchased editions of the governing standards remain authoritative.
| Element, mass % | Type 304 / UNS S30400 | EN 1.4301 / X5CrNi18-10 | Engineering meaning |
|---|---|---|---|
| Carbon (C) | ≤ 0.08 | ≤ 0.07 | Lower carbon reduces sensitization risk, but welded critical service often points to 304L / 1.4307. |
| Chromium (Cr) | 18.0–20.0 | 17.5–19.5 | Supports the passive oxide layer and general corrosion resistance. |
| Nickel (Ni) | 8.0–10.5 | 8.0–10.5 | Stabilizes austenite and supports formability and toughness. |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | Overlapping ceiling in the common specifications. |
| Silicon (Si) | ≤ 0.75 | ≤ 1.00 | Different ceilings can matter when a purchaser imposes tighter chemistry. |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | Same common maximum. |
| Sulfur (S) | ≤ 0.030 | ≤ 0.015 | EN 1.4301 uses a tighter maximum than the common Type 304 limit. |
| Nitrogen (N) | ≤ 0.10 | ≤ 0.11 | Small specification difference; check the actual heat analysis. |
Composition summary based on commonly published ASTM Type 304 and EN 1.4301 ranges. Standards can be revised, and requirements differ by product standard and order.
Do not compare strength numbers without matching product form and condition
Mechanical requirements are where “equivalent” becomes conditional. Cold-rolled sheet, hot-rolled coil, quarto plate, bar and tube can carry different minimums, test-piece orientations and thickness adjustments.
Outokumpu’s Core 304/4301 data illustrates the variation: its published EN minimums for cold-rolled flat product include Rp0.2 of 230 MPa, tensile strength of 540–750 MPa and elongation of 45%, while hot-rolled and plate values differ. The same datasheet separately reports ASTM minimum values because the standards and elongation references are not interchangeable.
Match grade → product standard → product form → thickness → delivery condition → test direction → inspection certificate. Only then compare yield, tensile strength, elongation or hardness.
Which EN standard should you cite for sheet, plate, bar or tube?
EN 1.4301 identifies the grade, not the complete product. A coil, a bright bar and a welded pressure tube can all carry the same material number while being delivered under different standards, dimensions, tolerances and mechanical-property tables.
| Document or code | Typical role | What the purchaser should add |
|---|---|---|
| EN 10088-1 | Lists stainless steels and their chemical compositions. | Do not use the grade list alone as the full delivery specification. |
| EN 10088-2 | Technical delivery conditions for sheet, plate and strip for general purposes. | Thickness, tolerance standard, condition, surface finish and inspection document. |
| EN 10088-3 | Technical delivery conditions for semi-finished products, bars, rods, wire, sections and bright products. | Exact long-product form, dimensions, condition, finish and property class. |
| Tube product standard | Separate standards cover welded or seamless tubes for pressure, mechanical or general-engineering service. | Name the exact tube standard, dimensions, test requirements and pressure-service obligations. |
Surface finish is part of material performance and appearance
For flat products, the finish code should be stated instead of relying on words such as “brushed” or “polished.” Common EN 10088-2 routes include 1D for hot-rolled, heat-treated and pickled product; 2B for cold-rolled, heat-treated, pickled and skin-passed product; and 2R for cold-rolled, bright-annealed product. Ground or brushed special finishes such as 2G and 2J require an agreed visual or roughness requirement where appearance is critical.
Finish is not merely decorative. Roughness, directional polishing, weld discoloration, embedded contamination and poor drainage can influence cleanability and corrosion behavior. A substitution that matches chemistry but changes finish can therefore fail the actual application.
Choose a practical grade and specification route
This selector provides a discussion starting point. It does not replace the governing design code, corrosion review, welding qualification, material standard or supplier confirmation.
Start with EN 1.4301
For general European fabrication in a mild environment, specify X5CrNi18-10 / 1.4301 with the applicable EN product standard.
- Name the product form and finish.
- Request an EN 10204 3.1 inspection certificate where traceability is required.
- Confirm actual heat chemistry and mechanical properties.
Validate the final material choice against the application, code and qualified process.
304 / 1.4301 is versatile, but it is not a universal chloride grade
Its chromium-rich passive film performs well in many atmospheric, food-processing and mildly corrosive services. Chlorides, deposits, crevices, elevated temperature and poor cleaning can destabilize that film and produce localized pitting or crevice corrosion.
The published PRE value for Core 304/4301 is about 18, reflecting the absence of molybdenum. Grade 316/1.4401 or low-carbon 316L/1.4404 is commonly evaluated when chloride resistance must be improved, but the correct choice depends on chloride concentration, temperature, pH, oxidizing conditions, surface finish, cleaning and geometry.
- Use 304/1.4301 for mild, well-drained environments after confirming cleaning chemistry.
- Avoid treating “stainless” as immune to pitting beneath deposits or in crevices.
- Compare 316L/1.4404 or higher-alloy grades for aggressive chloride service.
- Specify finish and post-fabrication cleaning because surface condition affects performance.
What changes when 304 or 1.4301 is welded?
Both grades are widely welded, but heat input can promote chromium-carbide precipitation in susceptible thermal cycles. The low-carbon 304L / 1.4307 route reduces that risk and is often preferred for welded equipment where corrosion resistance near the weld matters.
Check whether the WPS, code and service require 304, 304L, 1.4301 or 1.4307.
Record thickness, fit-up, gap, surface condition and restraint before setting parameters.
Use a qualified travel speed, focus and power window; avoid assuming one setting fits every product form.
Select shielding and backside protection to meet oxidation and corrosion requirements.
Verify penetration, porosity, discoloration and post-weld surface restoration.
Write a complete callout, not just “304 SS”
A complete material callout identifies the alloy, the governing product standard and the condition in which the product must arrive. This prevents an apparently similar grade from being accepted under the wrong chemistry, strength, finish or documentation route.
PER EN 10088-2
COLD-ROLLED SHEET, 2B FINISH
THICKNESS: [VALUE + TOLERANCE]
INSPECTION DOCUMENT: EN 10204 3.1
Minimum fields to place on the drawing or purchase order
- Steel name and material number
- Correct product standard and edition required by the project
- Product form, dimensions and tolerance standard
- Delivery condition and surface finish
- Inspection document type
- PMI, corrosion, impact or supplementary tests where required
- Any dual-certification requirement stated explicitly
What should the mill certificate prove?
EN 10204 defines inspection document types; it does not define the steel grade. The order should state both the product standard and the required document. For traceable procurement, compare the certificate with the physical marking and purchase order before release.
Test report
Manufacturer declaration with results based on non-specific inspection. It may not provide the heat-specific evidence required for critical traceability.
Inspection certificate
Includes results of specific inspection and is validated by the manufacturer’s authorized inspection representative independent of manufacturing.
Independent validation
Includes specific inspection results and validation involving both the manufacturer and an independent inspector designated by the purchaser or official regulations.
- Heat or cast number matches the product marking and every transferred certificate.
- Grade, product standard and ordered edition match the purchase order.
- Chemistry falls inside every grade claimed on a dual-certified certificate.
- Mechanical tests match product form, thickness and test direction.
- Finish, delivery condition and dimensional tolerances are documented.
- Certificate signatory and inspection-document type are valid for the order.
Validate the stainless steel, joint and laser process together
A designation tells you what the material should be. It does not prove that a particular joint, finish or laser parameter will meet the production requirement. Share the grade certificate, thickness, joint drawing, surface condition and acceptance criteria for a practical recommendation.
- Material grade and mill certificate
- Product form, thickness and dimensions
- Joint type, fit-up and required penetration
- Target appearance and inspection method
- Required cycle time or production volume
304 stainless steel equivalent EN material FAQ
Is EN 1.4301 exactly the same as AISI 304?
It is the closest and most common European comparison, but it is not an automatic one-for-one substitution under every product standard. Chemistry limits, mechanical requirements, test methods, product form, finish and certification must all satisfy the purchase order.
What does X5CrNi18-10 mean?
It is the composition-based EN steel name paired with material number 1.4301. X denotes high-alloy steel, 5 reflects the nominal carbon level used in the naming convention, CrNi identifies chromium and nickel, and 18-10 indicates approximate nominal contents.
Is 304L equivalent to EN 1.4307?
EN 1.4307 / X2CrNi18-9 is a common European comparison for 304L / UNS S30403. The lower carbon maximum improves resistance to sensitization after welding. Some 304L products may also be compared with 1.4306, so the exact standard and certificate still matter.
What is the EN equivalent of 304H stainless steel?
EN 1.4948 / X6CrNi18-10 is commonly cross-referenced with 304H / UNS S30409. It is intended for elevated-temperature strength under the relevant heat-resisting or creep-resisting product standard, not as a universal replacement for 1.4301.
Are SUS304 and EN 1.4301 interchangeable?
SUS304, Type 304 and EN 1.4301 belong to the same broad 18Cr-8Ni alloy family, but each designation must be ordered with its governing JIS, ASTM or EN product standard. Verify chemistry, properties and certification before substitution.
Should welded equipment use 1.4301 or 1.4307?
For many welded assemblies, the low-carbon 1.4307 / 304L route is preferred because it reduces carbide precipitation caused by welding heat. The final choice must follow the service environment, section thickness, welding procedure, code and corrosion requirements.
Which certificate should I request for EN 1.4301?
EN 10204 Type 3.1 is common where heat-specific test results and manufacturer validation are required. Type 3.2 adds independent inspection involvement. The project specification, regulation or purchaser determines the correct document.
Is 304 suitable for saltwater or coastal service?
It may show tea staining, pitting or crevice corrosion in chloride-rich conditions. Evaluate temperature, chloride level, wet-dry cycling, deposits, geometry, cleaning and finish. Molybdenum-bearing 316L / 1.4404 or a higher-alloy grade is often a better starting point.
Sources used for this guide
- British Stainless Steel Association — Related austenitic stainless steel grades. Grade comparisons and warning against assuming direct equivalence.
- Outokumpu Core range datasheet. Published grade mapping, product forms, composition, applications and mechanical-property data.
- ASTM Subcommittee A01.17. Current scope and status of ASTM A240/A240M and related stainless-steel product specifications.
- BSSA — Correct standards for stainless steel products. Roles of EN 10088-1, EN 10088-2 and EN 10088-3.
- BSSA — Specifying finishes for stainless steel flat products. EN surface-finish codes and processing routes.
- BSSA — BS EN 10204 test certificates. Explanation of inspection documents 2.1, 2.2, 3.1 and 3.2.
- ISO 10474:2013. International framework defining inspection document types for steel products.
- Outokumpu Core 304L/4307. Low-carbon grade characteristics, welding heat and intergranular-corrosion guidance.
- BSSA — Dual certification of stainless steel products. Practical limits and meaning of multiple grade certification.