As of 4 pm on Friday, January 19, 2018, the US Senate had not reached an agreement on the terms of a continuing resolution to keep the US government running. The US House passed a 30-day resolution on Thursday, but this must also pass the Senate and President Trump must sign it before midnight, January 19, 2018 to avoid a shutdown.
If this shutdown does happen and if it mirrors what happened with shutdowns in previous years, the immigration processes most impacted with be those involving the Department of Labor (DOL). Labor Condition Applications (LCAs) and PERM Labor Certification Applications cannot be filed during the shutdown as their funding is dependent on congressional appropriations. The US Citizenship and Immigration Services (USCIS), however, is a fee-based immigration benefit provider and it is not dependent on appropriations. As with prior shutdowns, we expect USCIS to continue operations and adjudicating cases.
The US State Department may also see a slow down or even cessation of visa processing until funding legislation can be passed.