ZIP Code software is being used by a website to help people identify the nearest clinic where they can get flu vaccinations.
Maxim Health Systems operates nearly 40,000 clinics across the US, all of which are now available for people seeking the flu jab.
The Centers for Disease Control and Prevention have advised people to get the vaccination as soon as they can, as it could also help protect against the swine flu virus, a second wave of which could impact the US during the autumn and winter months.
Bonnie Offit, MD and fellow of the American Academy of Pediatrics at the Children's Hospital of Philadelphia, said: "While we wait for safety and efficacy studies on the new H1N1 vaccine, we should all be getting our flu vaccines as early as possible this fall. Please don't wait - get vaccinated when clinics open."
People have the option of visiting info.findaflushot.com and entering their ZIP Code, which will provide address data relating to their nearest clinic.
The swine flu virus was first identified in Mexico and vaccines are being developed around the world.