ER308L vs ER316L: Complete Stainless Steel Welding Wire Guide

In stainless steel welding, ER308L and ER316L are two of the most commonly used filler metals. Both use a low-carbon design (carbon content ≤0.03%) to reduce the risk of intergranular corrosion, but they differ significantly in alloy composition, corrosion resistance, and application. Choosing the wrong welding wire can affect weld quality and may significantly shorten the service life of the weld in corrosive environments.

This article provides a systematic comparison of ER308L and ER316L across five key aspects: chemical composition, mechanical properties, corrosion resistance, applications, and cost. It also answers frequently asked questions about filler metal selection to help you make the right choice for your specific project.

ER308L is mainly used for welding 304/304L stainless steel, while ER316L is mainly used for welding 316/316L stainless steel. The key difference is that ER316L contains approximately 2.0–3.0% molybdenum (Mo), giving it better resistance to pitting and crevice corrosion in chloride-containing environments. ER308L generally has a lower material cost and is suitable for general stainless steel welding, while ER316L is usually preferred when higher corrosion resistance is required.

Comparison	ER308L	ER316L
AWS Classification	A5.9 ER308L	A5.9 ER316L
Matching Base Metal	304 / 304L	316 / 316L
Key Alloying Elements	Cr + Ni	Cr + Ni +Mo (Molybdenum)
Corrosion Resistance	Good	Excellent
Resistance to Chloride Pitting	Moderate	High
Crack Resistance	High	High
Cost Level	Low–Medium	High
Typical Industries	Food processing, architectural applications	Marine engineering, chemical processing, pharmaceutical

The fundamental difference between ER308L and ER316L is the presence or absence of molybdenum, which is the main reason for their different corrosion resistance.

ER308L typically contains approximately 19.5–22.0% Cr, 9.0–11.0% Ni, and ≤0.03% C. Its composition is designed to closely match 304 and 304L stainless steel.

ER316L typically contains approximately 2.0–3.0% Mo, 18.0–20.0% Cr, and 11.0–14.0% Ni. The addition of molybdenum significantly improves resistance to pitting and crevice corrosion, particularly in chloride-containing environments.

Both ER308L and ER316L have a carbon content of ≤0.03%. The “L” suffix indicates a low-carbon grade. Lower carbon content reduces chromium carbide precipitation during welding, helping minimize sensitization and the associated risk of intergranular corrosion.

Property	ER308L	ER316L
Yield Strength	~365 MPa	~385 MPa
Tensile Strength	~580 MPa	~590 MPa
Elongation	~38%	~36%

According to typical data from ESAB, ER316L has slightly higher yield and tensile strength than ER308L. However, this difference is generally not the primary consideration when selecting between the two welding wires.

In actual engineering applications, the strength difference between the two is usually not the key selection factor. For most stainless steel welding applications, both wires can provide sufficient mechanical performance. Corrosion resistance is the more decisive variable.

This is the most fundamental difference between ER308L and ER316L.

ER316L contains molybdenum, which significantly improves resistance to pitting corrosion. One comparative study found that ER316L welded samples had the lowest corrosion weight loss, at 4.39%, among the tested filler metals, showing the best performance in that specific corrosion test (Vardhan et al., 2025).

Another study focusing on dry storage canister applications further revealed the microstructural mechanism. In the specific welded specimens examined in that study, the δ-ferrite volume fraction in the ER316L weld was approximately 9.5% and appeared as discontinuous isolated regions, while the ER308L weld contained approximately 21.3% δ-ferrite in a continuous network structure (Kim et al., 2026).

This continuous ferrite network can act as an active pathway in chloride-containing environments, accelerating the propagation of stress corrosion cracking.

In simple terms: ER308L is suitable for general environments, while ER316L is generally more suitable for applications requiring higher corrosion resistance.

Application	ER308L	ER316L
Food and dairy processing equipment	Recommended	Can be used
Water storage tanks and piping systems	Recommended	Can be used
Architectural and decorative stainless steel structures	Recommended	Usually unnecessary
General industrial machinery	Recommended	Usually unnecessary
Marine platforms and ship equipment	⚠️ Not recommended	Recommended
Chemical and petrochemical equipment	⚠️ Depends on service medium	Recommended
Pharmaceutical and medical equipment	Can be used	Recommended
Piping systems carrying chloride-containing media	⚠️ Not the first choice	Recommended
304/304L base metal welding	Default choice	Can be used but usually unnecessary
316/316L base metal welding	Can be used for non-critical applications	Default choice

A practical rule is:

• For 304 stainless steel, use ER308L. 
• For 316 stainless steel, use ER316L.

ER308L can technically be used instead of ER316L for some 316 base-metal applications where corrosion resistance is not critical, but its corrosion resistance will generally be lower. 

For marine and chemical applications, ER308L is generally not recommended when the service environment demands the corrosion resistance associated with 316/316L.

ER316L generally has a higher procurement cost than ER308L because of its molybdenum content. Other factors, including certification requirements, inventory, and purchasing conditions, can also affect the final price.

Price Factor	Impact
Alloy composition	Mo content makes ER316L generally more expensive
Wire diameter	Different diameters may have different prices
Certification	Additional certifications may increase cost
Brand and origin	Different suppliers and origins have different pricing
Purchase volume	Larger quantities may receive better pricing
Lead time and freight	Logistics conditions affect total procurement cost

Therefore, welding wire selection should not be based only on the price per kilogram. Weld service life, maintenance costs, and potential downtime should also be considered.

When the required performance can be met, ER308L is the more cost-effective choice. In corrosive environments such as marine, chemical, and pharmaceutical applications, the additional material cost of ER316L may be offset by lower corrosion risk and reduced maintenance requirements.

For a real-time quotation, provide the required wire diameter, packaging, certification requirements, and purchase quantity.

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3 Key Questions Before Choosing

1. What is the base metal?

• If the base metal is 304 or 304L, ER308L is generally the standard choice.
• If the base metal is 316 or 316L, ER316L is generally the standard choice.

2. What is the service environment?

For environments involving chloride, seawater, acidic media, or coastal exposure, ER316L should generally be considered first.

For indoor applications or freshwater environments, ER308L is generally sufficient when the base metal and project requirements are compatible.

3. How important is material cost?

If the application has relatively mild service conditions and corrosion resistance requirements can be met with ER308L, its lower material cost can make it a more economical option.

1. What is ER308L welding wire used for?

ER308L is mainly used for welding 304 and 304L stainless steel and is also suitable for similar 300-series stainless steels, including 301, 302, 305, 308, 321, and 347 in appropriate applications.

Typical applications include food processing equipment, brewery piping, pharmaceutical equipment, water tanks, architectural structures, and general stainless steel manufacturing.

Its low carbon content helps reduce the risk of sensitization and intergranular corrosion after welding.

2. Can you use ER308L to weld 316 stainless steel?

Yes, ER308L can technically be used to weld 316 stainless steel under certain conditions. However, because ER308L does not contain molybdenum, the resulting weld metal generally has lower corrosion resistance than a weld made with ER316L.

If 316 stainless steel is selected because chloride or chemical corrosion resistance is important, ER316L is generally preferred. If corrosion resistance is not a critical requirement, ER308L may be technically acceptable in some applications.

3. Is ER316L stronger than ER308L?

Typical weld-metal data shows that ER316L can have slightly higher yield and tensile strength than ER308L. However, this difference is usually not the main factor in selecting between the two.

The base-metal match and service environment are generally more important considerations.

4. Which is better for corrosive environments, ER308L or ER316L?

For applications requiring higher resistance to chloride-induced pitting and crevice corrosion, ER316L is generally preferred.

The main reason is its approximately 2.0–3.0% molybdenum content, which improves localized corrosion resistance.

The final selection should still consider the base metal, service medium, temperature, and specific project requirements.

5. Can you use ER308L to weld stainless steel to mild steel?

ER308L can technically be used in some stainless-steel-to-carbon-steel welding situations, but it is generally not the preferred filler metal.

Because of dilution from the carbon steel, the weld may develop martensitic structures that can be harder and more brittle. ER309L is commonly used for stainless steel to mild steel or carbon steel joints.

If ER308L is the only available option, it may be considered for limited or non-critical situations, but it should generally be avoided for load-bearing or critical structures.

ER308L is an economical general-purpose stainless steel filler metal suitable for 304 base metal and general service environments. ER316L, with its molybdenum-enhanced corrosion resistance, is commonly selected for demanding environments such as marine, chemical, and pharmaceutical applications.

The core principle when choosing between them is simple: match the welding wire to the base metal and service environment rather than looking only at the price.

[1] Vardhan, A., Mishra, A., & Kumar, G. (2025). Investigation of the Effects of Filler Wires on the Microstructural and Mechanical Properties of GTAW-Welded IS2062E350C Pressure Vessel Steel. Journal of the Chinese Society of Mechanical Engineers, Series C, 46(5), 517–526.

[2] Kim, S., Kim, G., & Song, S.-W. (2026). Selective corrosion of δ-ferrite in austenitic stainless steel welds under wet–dry cycling: Influence of surface temperature for dry storage canister applications. Nuclear Engineering and Technology, 58(5), 104141. DOI: 10.1016/j.net.2026.104141.