H1 B extension application receipt number

[girmaji]

Hi,

My employer is going to apply for my H1 extension in a week.

I would like to know whether USCIS office gives us an acknowledgement number after they receive my application.

What is the proof of receipt by USCIS office for my application that is sent via USPS/Fed EX courier?

What is difference between Acknowledge number, File number and Receipt number and what are the time lines associated with these terms ?

Please clarify.

Regards.

Kiran Girmaji.

[Nesh]

Fed EX will give you Tracking number which you can track on its site and get to know when was document received..

Receipt Number is generated by USCIS - Number on your notice of receipt and can track your case on USCIS site.