Josh Tarling abandoned the Vuelta a España early on stage six on Thursday, leaving Netcompany-Ineos with seven riders.
The Welshman started the Spanish Grand Tour on Saturday just over a week after his brother Finlay died after he was hit by a non-race driver at the Volta a Portugal.
He finished third on the opening day's time trial in Monaco, just four seconds behind the winner, Tadej Pogačar (UAE Team Emirates-XRG).
He spent the next few stages working for Oscar Onley, who sat in fifth overall after stage five.
Netcompany-Ineos posted on social media: "Josh Tarling’s Vuelta has come to an end as he’s decided to stop. We couldn’t be prouder."
Later, the team added: "After the unimaginable loss of his brother Fin, Josh showed incredible courage in starting La Vuelta.
"We are immensely proud of him, and he now returns home to be with his family with the full love and support of everyone at Netcompany-Ineos. Family comes first. Always."
Ahead of the race, Tarling's parents, Dawn and Michael, posted on Instagram that he heading to the Vuelta with their support.
"He has chosen to do so in honour of his brother Fin, with the full support of his family, surrounded by a team who have been incredibly supportive of whatever decision he made," they wrote.
"I could not have wished for two boys who were closer growing up and into adulthood we have watched with pride as Joshua has been the most loving and supportive big brother to Fin. Following this devastating news he has been an incredible strength for us all.
"Finlay was so incredibly proud of his big brother, and would be watching nose to the TV and shouting as he competed.
"So it is right that Josh honours that love."
A GoFundMe page created in memory of Finlay Tarling, aiming to raise money to support young Welsh riders in the future, has raised over £90,000 in less than a fortnight.
