Yes, you can sit for the U.S. citizenship test with an expired green card, but it is advisable to renew your green card before applying for naturalization. While an expired green card does not disqualify you from taking the test or completing the naturalization process, U.S. Citizenship and Immigration Services (USCIS) generally expects lawful permanent residents to maintain valid documentation throughout the process. If your green card is expired, USCIS may require you to renew it, as a valid green card is often needed for identification purposes, employment, and travel during the naturalization process.
To avoid delays or complications, it’s best to renew your green card before applying for citizenship.