COBOL default date format is YYYYMMDD. Below is the list of COBOL intrinsic functions that help you get various Date related things.

COBOL List of DATE Functions

CURRENT-DATENoneAlphanumericCurrent date and time
DATE-OF-INTEGER1 integerIntegerStandard date equivalent (YYYYMMDD) of integer date 5
DATE-TO-YYYYMMDD1 or 2 integerIntegerYYYYMMDD date converted from YYMMDD date
DAY-OF-INTEGER1 integerIntegerYYYYDDD date equivalent of integer date 5
DAY-TO-YYYYDDD1 or 2 integerIntegerYYYYDDD date converted from YYDDD date
FACTORIAL1 integer, intIntegerFactorial of int
INTEGER1 numeric, numIntegerThe greatest integer not greater than num
INTEGER-OF-DATE1 integerIntegerInteger date 5 equivalent of standard date (YYYYMMDD)
INTEGER-OF-DAY1 integerIntegerInteger date 5 equivalent of date in YYYYDDD format