The UCI International Center advances and facilitates international engagement at UCI to enhance the academic and personal experience of the international community. Their website has information for postdoctoral scholars regarding visas, your immigration status, and travel. It should also be the first place you go to upon arriving in the US when you start working at UCI (a process called checking-in).
The International Center is located at G302 UCI Student Center, Irvine, CA 92697-5255.
Social Security Number
Postdoctoral scholars who are employed by UCI must obtain a Social Security Number (SSN) before they can be paid. To apply for an SSN, head to your nearest Social Security Office. Remember to bring your passport, DS-2019, I-94, and any other documentation to indicate that you are working in the US. It takes about a day for your US entry status (for the I-94) to be updated, so plan your visit accordingly.
Note that the Social Security Card will be mailed to you in 1-6 weeks, which means you need to provide an address. If you are yet to find housing at this point, have an alternative address for it to be mailed to. It is not a good idea for it to be mailed to your temporary accommodation.
When you receive your SSN, you need to report it to your Department Coordinator. Keep your SSN safe, and do not give it to anyone who does not need it. It is common for banks and landlords to ask for your SSN.
Postdocs who intend on traveling outside of the US must make the necessary arrangements for re-entry to the US. A travel signature is required on your DS-2019. This is an official indicator that you are still a scholar at UCI. To obtain a travel signature, complete and submit a Scholar Travel Form along with your DS-2019 to the International Center. Note that it takes around 5 business days for this process. Generally, your travel signature is valid for one year. After it expires, you will need to obtain another travel signature before you can re-enter the US.
After you return to the US, check that your entry status has been correctly updated (I-94).