For the second consecutive year, the 27-year-old Romanian will end the year as the top-ranked player on the WTA Tour regardless of results.
Simona Halep will finish 2018 at the top of the WTA rankings, topping the year-end standings for the second consecutive season.
The Romanian has enjoyed another successful year, including winning her first grand slam title at the French Open, and she is once again ending the campaign on top of the pile.
Halep will be presented with the trophy to mark her achievement at the WTA Finals in Singapore.
2018 has been incredible. I am so proud to finish as @WTA year-end No.1 for the second time!— Simona Halep (@Simona_Halep) October 15, 2018
Thanks to @darren_cahill and all my team for making these memories with me and being by my side pic.twitter.com/zvj6PXJKi4
"Finishing the season as the WTA world number one last year was a huge honour for me," said Halep.
"To do it for a second time in 2018 feels like a special achievement, especially having also won my first grand slam this year.
"To be able to see my name again alongside the other legends who have achieved the year-end number one ranking makes me very proud."
Halep has struggled with a back issue in recent weeks and she is hopeful to be able to take part in this week's Kremlin Cup in order to then challenge in Singapore.
She added: "I'm doing physio to try to make [my back] stronger, but I haven't practiced 100 per cent yet.
"If I can't play here, I'm very doubtful that I will be able to play in Singapore. I don't know now, but for sure I will take a decision for my health first."