The aim of the project is to encourage alternative ways to travel to work in a bid to reduce congestion and emissions.
Once an employee registers at www.welhatcarshare.com, they are provided with details of anyone who drives, walks or cycles a similar route to work.
They can then decide whether to share with someone from their own organisation or with one of the partner organisations signed up to the scheme.
Cllr Mandy Perkins of Welwyn Hatfield Council said: “The benefits of car sharing are immense. In addition to environmental benefits, car sharing can save employees money – a shared car means shared petrol costs.”
Employers in the areas wanting to know more can call the council’s transport department on 01707 357550.