After defeating Argentina 1-0 after extra time in Sunday's final in New Jersey, thanks to Ferran Torres' decisive goal, Spain arrived in Madrid with the World Cup trophy they last won in 2010.
The squad, led by coach Luis de la Fuente and captain Rodri, first visited Zarzuela Palace, where King Felipe VI, Queen Letizia, Princess Leonor and Princess Sofia congratulated the players on their remarkable success.
Addressing the team, King Felipe praised their performances throughout the tournament.
"You have shown your grit, your resilience and your courage, always backed by your technical skill, your control and command of the game, combining head and heart," he said.
The king also highlighted the unity within the squad during their journey to lifting the expanded 48-team World Cup.
The celebrations continued with a visit to Prime Minister Pedro Sanchez before the team embarked on an open-top bus parade through central Madrid, where around a million supporters were expected to line the streets.
Rodri proudly carried the World Cup trophy as the players arrived home and later reflected on what the triumph meant to him.
"I've always said it, winning with your country is the most beautiful thing there is, above all a World Cup," said the Manchester City midfielder.
"This generation grew up watching Iker Casillas and Andres Iniesta lift the cup and that we can do it today is the biggest thing you can do in football."
For many of Spain's younger fans, this was their first opportunity to celebrate a men's World Cup triumph, having been too young to witness Iniesta's famous winner against the Netherlands in South Africa in 2010.
Final hero Ferran Torres admitted the celebrations had only just begun.
"I'm very happy to see how excited all of the children are and to have the parade and celebrate with all of the Spaniards," he said. "I'm flying, literally."
Supporters had already gathered across Madrid long before the team's arrival, with many celebrating through the night before making their way back to the city's main streets for the victory parade, which ended at the famous Cibeles Square.
Prime Minister Sanchez also looked ahead to the future after Spain maintained its perfect record in World Cup finals.
"It's two for two," he said. "Why not dream of a third in 2030, especially with Spain as hosts?"
Spain will have the chance to defend their title on home soil in four years' time when they co-host the 2030 World Cup alongside Portugal and Morocco.
The latest success also made history for Spanish football, with the country's women's team having won the 2023 Women's World Cup. Spain is now the first nation to hold both the men's and women's World Cup titles at the same time.
Spain's triumph completed an impressive tournament that included victory over France in the semi-finals before overcoming Lionel Messi's Argentina in the final, as De la Fuente's side produced another disciplined and composed display to lift their second World Cup trophy.