The INS' Delaware office is a subdivision of the Philadelphia, Pennsylvania, office. The Dover office is located at 1305 McD Drive, Dover, DE 19901. The office is open from 8:00am until 4:00pm Monday through Friday. WARNING: The Dover Office does not accept cash payments. Have a check or money order ready in the exact amount. Delaware residents may also visit the Philadelphia, PA, district office located at 1600 Callowhill Street; Philadelphia, PA 19130. The office is open from 7:30am until 3:00 pm Monday, Tuesday, Wednesday, and Friday. The office closes at 11:00am on Thursday. WARNING: The INS provides customers with a ticket number. Only a limited number of tickets are available per day. Tickets begin to be distributed at 7:30am. It is recommended that you appear early at this office. It may take several hours for your number to be called. Click here to find the INS USCIS Immigration Forms you need! Click Here for Immigration Information, Reports, and Frequent Questions Click here to find the immigration books and manuals you need!