# 303 stainless steel equivalents

303 stainless steel is nearest to EN 1.4305 (X8CrNiS18-9), JIS SUS303 and China GB Y12Cr18Ni9. These are nearest equivalents, not identical grades: the governing standard or mill certificate decides.

| System | Designation |
|---|---|
| AISI / ASTM / SAE | 303 |
| EN steel name | X8CrNiS18-9 |
| EN steel number | 1.4305 |
| JIS | SUS303 |
| China GB | Y12Cr18Ni9 |

Family: Austenitic stainless, free-machining

## What it is

A free-machining austenitic stainless steel. Added sulphur forms inclusions that break the chip, making it the easiest austenitic grade to machine. The trade-off is lower corrosion resistance than 304 and poor weldability.

## Typical uses

Screw-machine and CNC lathe parts, shafts, bushings, fittings, nuts and bolts, and valve parts where welding is not needed.

## Machining notes

The best choice of the austenitic grades for high-volume turning. Chips break more easily, but it still work-hardens, so do not let the tool rub.

## Related grades

- 304 stainless steel (1.4301): Better corrosion resistance and weldability

Equivalents are nearest matches, not identical grades. The governing standard or mill certificate decides.

## FAQ

**What is the European equivalent of 303 stainless steel?**
The nearest EN grade is 1.4305, steel name X8CrNiS18-9.

**What is the JIS equivalent of 303 stainless steel?**
The nearest Japanese grade is SUS303.

**What is the Chinese GB equivalent of 303 stainless steel?**
The nearest Chinese GB grade is Y12Cr18Ni9.

**Is 1.4305 the same as 303?**
1.4305 (X8CrNiS18-9) is the nearest European equivalent of 303, not an identical grade. Composition limits and required properties differ in detail, so check the governing standard or the mill certificate when it matters.

**What is 303 used for?**
Screw-machine and CNC lathe parts, shafts, bushings, fittings, nuts and bolts, and valve parts where welding is not needed.

Source page: https://machinistcharts.com/material/303-stainless/
Updated: 2026-10-06
Publisher: MachinistCharts (https://machinistcharts.com)