Swedish driver Oliver Solberg, who led the Chile Rally from start to finish, completed his second WRC victory on Sunday, ensuring that Toyota secured a record-equalling 10th team title.
Solberg and co-driver Elliott Edmondson saw off nine-time world champion Sebastien Ogier by 16.6 seconds, with Adrien Fourmaux taking third for Hyundai, 33.3 seconds from the lead.
"It's been an unbelievable weekend," said Solberg, 24, who is the son of 2003 champion Petter Solberg.
"It's been up and down, but the team always supported, always pushed, always believed.
"Finally a little bit of luck was on my side, and I could just focus on my job and do my thing. The little details matter, and this weekend was a perfect, perfect weekend."
Toyota needed seven points to wrap up their sixth successive manufacturers' championship, extending an unbeaten run dating back to 2021.
Toyota's 10th title puts them level with Lancia as the most successful manufacturer in WRC title history.
Welshman Elfyn Evans, also in a Toyota, is closing in on his first drivers' title, even though he could only finish fifth in Chile.
Evans has 230 points, 17 ahead of the Finn Sami Pajari, in a Yaris, who finished fourth. Solberg is third on 209.
The season has two events still scheduled in Sardinia and Saudi Arabia, although doubts remain over whether the latter will still go ahead.