Tenaris S.A.

Transaction in Own Shares • Jul 26, 2025

Giovanni Sardagna Tenaris 1-888-300-5432 www.tenaris.com

Weekly Report (July 21, 2025 – July 25, 2025) on the First Tranche of Tenaris Share Buyback Program.

Luxembourg, July 25, 2025. - Tenaris S.A. (NYSE and Mexico: TS and EXM Italy: TEN) ("Tenaris") announced today that pursuant to its First Tranche of the USD1.2 billion Share Buyback Program announced on June 6, 2025, covering up to USD 600 million to be executed in the open market, it has repurchased the following ordinary shares from July 21, 2025 to (and including) July 25, 2025:

Date	Trading Venue	Shares Purchased	Weighted Average Price (EUR)	Purchases in EUR	Reference FX	Purchases in USD
21-jul-25	MTAA	239,008	15.9705	3,817,077	1.1696	4,464,454
21-jul-25	CEUX	80,956	15.9468	1,290,989	1.1696	1,509,941
22-jul-25	MTAA	250,000	15.9919	3,997,975	1.1724	4,687,026
22-jul-25	CEUX	100,000	15.9909	1,599,090	1.1724	1,874,693
23-jul-25	MTAA	100,000	16.2708	1,627,080	1.1735	1,909,378
24-jul-25	MTAA	100,000	16.2996	1,629,960	1.1765	1,917,648
25-jul-25	MTAA	100,000	16.1922	1,619,220	1.1729	1,899,183
		969,964	16.0639	15,581,391		18,262,323

From July 21, 2025 to (and including) July 25, 2025, the Company has purchased a total of 969,964 ordinary shares for a total consideration of €15,581,391, equivalent to USD18,262,323.

As of July 25, 2025, the Company held in treasury 21,028,303 ordinary shares equal to 1.96% of the total issued share capital.

Tenaris intends to cancel treasury shares purchased under the Programs in due course.

Details of the above transactions, are available on Tenaris's corporate website under the Share Buyback Program Section https://ir.tenaris.com/share-buyback-program.

Some of the statements contained in this press release are "forward-looking statements". Forward-looking statements are based on management's current views and assumptions and involve known and unknown risks that could cause actual results, performance or events to differ materially from those expressed or implied by those statements. These risks include but are not limited to risks arising from uncertainties as to future oil and gas prices and their impact on investment programs by oil and gas companies.

Tenaris is a leading global supplier of steel tubes and related services for the world's energy industry and certain other industrial applications.