Delaware is offering a free E-ZPass transponder to all motorists who sign up before the end of the year.

A Delaware-issued E-ZPass is valid at all states' E-ZPass tolling facilities, although some state-specific discounts are only available to motorists who obtain a transponder in that state. For example, Delaware River Port Authority toll bridges offer a 50-percent discount to senior citizens who use a New Jersey-issued E-ZPass transponder.

A Delaware E-ZPass transponder normally costs $15 to obtain, but requires no annual fee. New Jersey and Pennsylvania issue transponders free to motorists who link their accounts to a credit card, but charge an annual fee ($12 in New Jersey and $3 in Pennsylvania).

Delaware E-ZPasses are available at toll plazas in the state, at the website, or by calling 888-397-2773.

- Paul Nussbaum