Treasury sets copper pound at 639.7619 dollars for mining royalty

The Ministry of Finance set the average price of a pound of copper at 639.7619 US$/lb for the July-September quarter of 2026, a figure that serves as the basis for the quarterly adjustment of the monthly provisional payments of the mining royalty. The measure is contained in exempt resolution No. 688, issued on October 21, 2026, and published in the Official Gazette No. 44,586 on Thursday, October 29, 2026, in Section I (CVE 2891303). The act bears the signature of the Minister of Finance, Jorge Antonio Quiroz Castro.

The framework for the decision is Law No. 21,591, on the Mining Royalty, published in the Official Gazette on August 10, 2023, which created a tax called the Mining Royalty intended to tax mining operators. Article 7 obliges taxpayers to make a monthly provisional payment equivalent to a percentage of the gross income received or accrued from the sale of mining products.

The same article, in its fourth paragraph, orders that these provisional payments be adjusted quarterly according to the variation in the average price of a pound of copper. To operationalize the rule, the law charges the Ministry of Finance with setting the average price of each quarter via resolution, using the quotation value on the London Metal Exchange from the immediately preceding quarter as a reference. Exempt resolution No. 688 fulfills this mandate for the third quarter of 2026.

How the reference price was calculated

The calculation was based on copper prices officially published by the Chilean Copper Commission (Cochilco). The parameters used were as follows:

• Cash and nominal price of the London Metal Exchange.
• Period considered: from July 1, 2026, to September 30, 2026, both dates inclusive.
• Database: daily copper price series disseminated by Cochilco.
• Method: quarterly average of those daily values, rounded to the fourth decimal.
• Complementary result: the variation for the third quarter of 2026 was calculated using the obtained value.

The text resolves succinctly: “The average price of a pound of copper for the July - September quarter of the year 2026 is set at 639.7619 US$/lb (US cents per pound of copper), for the purposes of the quarterly adjustment of the monthly provisional payments established in Article 7 of Law No. 21,591.”

Scope on the tax burden of mining companies

The fixed value is not a projected market price, but rather a regulatory parameter: it operates as an update factor for the monthly provisional payments that obligated mining operators must remit to the treasury. As the quarterly average rises, the readjustment increases the provisional amount to be paid for each operation, thereby advancing the cash impact of a tax burden that is later regularized in the annual declaration.

The regulation is further supported by DFL No. 1/19,653, of 2000, from the Ministry General Secretariat of the Presidency, and by Law No. 19,880, which establishes the bases for administrative procedures, as well as Supreme Decree No. 38, of March 11, 2026, from the Ministry of the Interior, and Resolution No. 36, of 2024, from the Comptroller General of the Republic. The act concludes with the formula “Be it noted, published, and archived.”

The publication completes the quarterly cycle that began with the entry into force of the royalty and provides legal certainty to companies regarding the applicable factor between July and September. For mining operators, the relevant detail is that the readjustment is applied to gross income, meaning its effect is proportional to the sales volume of each site and not to the operational result.

Source: Official Gazette of the Republic of Chile, No. 44,586, Thursday, October 29, 2026, Section I, pgs. 1-2 (official reference: CVE 2891303).