The Bcl6-Blimp-1 axis plays a critical role in follicular T helper (Tfh) cell fate determination; however, the regulation of CXCR5 expression during Tfh maturation is still elusive. Zhu et al. report that the Bhlhe40-Pou2af1 pair regulates optimal expression of CXCR5 and Tfh cell migration into germinal centers without affecting Bcl6 induction.