Changing an E-3 visa to dual citizenship with the United States is similar to entering college right after kindergarten; it's impossible if you skip the many steps and stages in between. An E-3 visa is a non-immigrant visa, therefore it in of itself cannot even lead to a green card, which is a necessity for obtaining U.S. citizenship. The holder of an E-3 visa must first change the status of his visa to a permanent one, obtain a green card and live as a legal permanent resident (LPR) in the United States for five years before being qualified to apply for citizenship.
Change the status of your E-3 visa. An E-3 visa is a temporary work visa for Australian citizens wishing to work in a specialty occupation for a designated period of time. In other words, the visa expires after 24 months. To obtain a permanent resident card (green card), you must alter the status of the visa. There are virtually only two possible ways to adjust your status from a non-immigrant visa to a permanent resident: obtain permanent employment from an U.S. employer or marry an U.S. citizen. All other visa types, including student, do not qualify you for permanent residency. If you obtain a permanent job offer, your employer must file Form I-140 Immigrant Petition for Alien Worker with the U.S. Citizenship and Immigration Services (USCIS) on your behalf. After the approval of the petition, you will be contacted to attend an interview and required to submit multiple forms. If you marry an U.S. citizen, I-130 Petition for an Alien Relative must be filed with the USCIS along with all necessary documents.
Apply for permanent residence. Once you are eligible to obtain a green card (permanent worker or spouse of U.S. citizen) submit Form I-485 Application to Register Permanent Residence with the USCIS. The application form must be accompanied by the $1,010 application fee, copy of passport visa pages, two passport-style photos, copy of birth certificate and a letter of employment from employer if applying based on permanent job offer or a copy of the I-130 petition approval if applying as a spouse of an U.S. citizen.
Complete the permanent residency requirement for naturalization. Before an LPR can apply for citizenship, he must fulfill the residency requirement of five years--three years if the green card was obtained through marriage. During the residency period, the LPR must be present in the United States for 30 months and cannot be absent from the United States for periods exceeding six months without obtaining a re-entry permit (I-131). If an absence of one to two years is required, the LPR must obtain both a re-entry permit and N-70 Application to Preserve Residence for Naturalization Purposes. The N-70 form can only preserve residence for up to two years of absence; an LPR loses status if absent for more than two years.
Apply for citizenship. Only when the residency period is completed can the applicant then apply for citizenship. To apply, file N-400 with the USCIS. Once your application is approved, you will be notified of when and where to attend a citizenship interview and take the U.S. civics (history and government) exam. Australians are except from the English language part of the examination. If the interview is passed, you will be notified of where and when to attend the citizenship ceremony where you will swear the oath of allegiance and pledge the flag. After the ceremony you will be awarded your certificate of citizenship.