Arriva UK operates a bus from Watford to Redbourn every 15 minutes. Tickets cost $5 - $8 and the journey takes 41 min. 2 other operators also service this route.
How to get from Watford to Redbourn
From Watford, Clarendon Road bus to St Albans, St Peter's Street then line 35 bus to Redbourn, Lamb Lane. 1 h 9 min £5. From Watford taxi to Redbourn. 16 min £54. From Watford drive to Redbourn. 16 min £2.