According to TV Zone the overnight ratings for last nights Doctor Who: Fugitive of the Judoon averaged 4.21m.  The official 7 day consolidated ratings will be available in a weeks time.

RATINGS: Last night's #DoctorWho (Episode 5) averaged 4.21m from 7:10pm on BBC One.

Overnights for the series so far…
Episode 1: 4.88m
Episode 2: 4.60m
Episode 3: 4.19m
Episode 4: 4.04m
Episode 5: 4.21m https://t.co/lu2brq52zA

— TV Zone (@tvukzone) January 27, 2020