My green card is expired or about to expire and I am already eligible for citizenship. Do I need to renew the card first?

Not always. You can generally file Form N-400 for citizenship even if the physical green card is expired. A properly filed N-400 receipt currently extends the card’s validity for 24 months when used with the card. You may still need Form I-90 or temporary proof of permanent resident status if the card is lost or you need longer evidence. Conditional residents should not use Form I-90 to remove conditions.