To add a new driver to a OneBeacon auto insurance policy, it is generally necessary to provide specific information about the new driver, such as their name, date of birth, and driver's license number. This process can usually be initiated through a few different channels. One option is to log in to the policyholder’s account on the OneBeacon website, where they can find options to manage their policy online. Alternatively, policyholders may also consider contacting their insurance agent or representative, who can assist with the process and guide them through any required documentation or changes. It is important to note that the addition of a new driver may impact the premium of the auto insurance policy. Therefore, reviewing the potential changes in coverage or costs is advisable. For more accurate details, individuals should visit OneBeacon's official web page, where they can find specific guidance that pertains to their policy.