Tulis terus kanggo paragraf iki - Republic Records dikonfirmasi ing April 2015 sing remix saka "Bad Blood" bakal dadi single kaping papat saka "1989". Versi remix sing nampilake rapper Kendrick Lamar dirilis tanggal 17 Mei 2015, kanggo didownload digital dening Big Machine Records. Rilis single iki didhukung dening perdana video musik ing 2015 "Billboard" Music Awards
. lan "Bad Blood" mengaruhi radio hit kontemporer AS tanggal 19 Mei 2015, ing sangisoré Big Machine lan Republic Records. Lagu iki dirilis ing radio hit kontemporer Italia tanggal 12 Juni 2015, liwat Universal Music Group.