From the 1st September 2015:
388 – Just morning and afternoon school runs, term-time only.
378 - Hertford - Monday, Wednesday & Friday. Leaves Tewin at 11.35, arrives in Hertford at 11.50. Return: leaves Hertford at 13.20, arrives in Tewin at 13.35.
204 - Morrisons and Welwyn Garden City - Tuesday, Thursday & Friday. Leaves Tewin at 11.05, arrives at Morrisons at 11.12 and WGC at 11.24. Return: leaves WGC at 13.45, leaves Morrisons at 13.53, arrives in Tewin at 14.04.