Remember to keep a copy of everything you send to USCIS.
You will send Form I-485 and all supporting documents to a lockbox facility. They will be forwarded to the USCIS Service Center for processing. Please confirm the mailing address by checking the I-485 instructions before mailing.
If you are filing Form I-485 together with Form I-140, send your documents to the USCIS Dallas Lockbox:
P.O. Box 660867
Dallas, TX 75266
If you live in Indiana and are filing Form I-485 based on a pending or approved Form I-140, you must file with the USCIS Phoenix Lockbox. Include a copy of Form I-797, which shows that your Form I-140 has been receipted or approved.
P.O. Box 21281
Phoenix, AZ 85036