Nicholas Williams Arthuer (born 12 July 2002) is a Spanish professional footballer who plays as a winger for La Liga club Athletic Bilbao and the Spain national team.

He was a member of their 2022 FIFA World Cup and UEFA Euro 2024 squads, scoring and being named man of the match in the final of the latter as Spain won the tournament.

[5] He made his first-team—and La Liga—debut on 28 April the following year, coming on as a second-half substitute for Jon Morcillo in a 2–2 home draw against Real Valladolid;[6] his brother Iñaki also came off the bench ten minutes later.

[16][17] Athletic made a strong start to the 2023–24 La Liga season with Williams providing numerous scoring chances, mainly from the left wing as coach Ernesto Valverde settled on a front line featuring Iñaki on the opposite flank and Gorka Guruzeta in the centre, supported by Oihan Sancet.

[28] He received his first call-up to the senior squad, coached by Luis Enrique, for 2022–23 UEFA Nations League fixtures in September 2022, and made his debut in a 2–1 home defeat against Switzerland.

[30] He subsequently was called up for the 2022 FIFA World Cup,[31] where he made four appearances with one start as Spain were eliminated in a penalty shootout by Morocco in the round of 16.

[8] He scored the opening goal of the final against England with a low left-footed shot following a pass from fellow winger Lamine Yamal; Spain won 2–1 to claim the trophy for a record fourth time[35] with Williams named as Player of the Match.