Between back to school shopping and fashion week, September is truly the month of fashion reinventions and celebrating personal style—and who are more stylish than our resident reigning pop stars?

PopCrush Best Dressed is a month-long competition to determine the ultimate style stars of 2017!

In Round 1, edgy pop foursome Fifth Harmony—known for their coordinated onstage outfits and chic award show looks—go up against breakout pop star Halsey, a rising style icon in her own right.

The battle begins right now: Place your vote between Fifth Harmony and Halsey for 2017’s Best Dressed! Round 1 ends Monday, September 18 at 11:59 p.m. EST.

Halsey's Hottest Instagram Photos: