ITA and RMI jointly developed the Assessment Criteria for Tin Smelting Companies (v2 2019) with the agreed aim to clarify upstream and downstream understanding of due diligence and a standard aligned with the OECD Guidance.

Following implementation by both organisations of assessments against the Criteria between 2023 and 2025, RMI announced in December 2025 that it will cease conducting assessments against the Criteria effective 1st January 2026. This RMI decision was taken due to limited uptake of assessments against the Criteria, and to focus for tin exclusively on RMI’s own RMAP Tin and Tantalum Standard (2017).

To maintain audit choice for tin smelters, ITA will continue to offer and manage assessments against the Tin Criteria under the Tin Code Assurance Process which has strong uptake.

Both organisations are committed to avoiding duplicated assessments and will actively explore appropriate means to achieve that throughout 2026.

For questions about this update or assessments against the Tin Criteria, please contact: Sonia Marsh (sonia.marsh@internationaltin.org), Daniel Zamora (daniel.zamora@Internationaltin.org).

The International Tin Association (ITA) is delighted to announce that ARCHE Advisors has joined the Tin Code’s list of registered auditors. This gives ITA members an additional choice of qualified ISAE 3000 auditors to support their Tin Code Assurance.

ARCHE Advisors bring over 25 years of global experience managing human rights audit programs, supply chain mapping, and ESG risk assessments. With a team of 280+ assessors operating in over 150 countries, they have conducted tens of thousands of ethical audits worldwide, including more than 6,000 audits in 2024 alone.

ARCHE’s responsible minerals services are backed by qualified experts who are also approved auditors for RMI, Copper Mark, LBMA, and ICMM, with direct ESG and due diligence assessments experience across 30+ countries. Auditors’ expertise spans responsible sourcing, traceability, and advisory projects across minerals, agriculture, and textiles.

The ITA Sustainability Team is excited to keep driving forward the implementation of the Tin Code Assurance System, helping advance responsible practices throughout the tin supply chain.

Explore publicly available Tin Code audit reports on our website.