HHSC is affiliated to Hertfordshre ASA. HHSC swimmers compete in the following County events:
- The Hertfordshire County Championships which are held in January and February.
- The Masters competition held in June.
- Younger swimmers also have the opportunity to compete in the Development Meet in November
HHSC is also affiliated to East Swimming which includes Hertfordshire, Bedfordshire, Cambridgeshire, Essex, Norfolk and Suffolk. HHSC swimmers compete in the following Regional events:
- The championships held in May.
- The Winter Championships which are held in November
Swimmers who achieve their national qualification times can swim in the National Championships for their age group in July.