any one pliz tell me!thanx

There is no term as CS deadline for a match season.

Applications start from 1st september.

Technically you can start applying even if you have score of any Step exam.
But not practical.
Few USMGs start with step 1 and CS scores and do CK in the meantime..september/oct/nov/dec...

But IMGs usually come prepared with ECFMG certificate BEFORE 1 SEPTEMBER.

And I think you are asking about Which date should be latest for CS so that you get ECFMG certificate by 1st September-
answer =

14th MAY SURE
16th July Sure if USMLE declares your date early.

My answer= 16 July

See the Table and you will understand better.

http://usmle.org/Examinations/step2/step2cs_reporting.html

hey thanx for the info...my CS is on 18 july wich means then i wont have my certificate ready by july!!! so im i doomed to no residency? i keep refreshing the schedule to see if i can get a june date hop i will