Besides the serial number, another way to date your Rolex watch is to look at the clap code, located on the inner-side of the clasp buckle. Clasp codes can give you a better understanding of when a Rolex watch was made, but also realize that clasps can easily be changed after production. The list below was not provided by Rolex, but by collectors, so some codes (especially earlier ones) may not be completely accurate.
| YEAR OF MFG. | CODE |
| 1976 | VA |
| 1977 | VB |
| 1978 | VC |
| 1979 | VD |
| 1980 | VE |
| 1981 | F |
| 1982 | G |
| 1983 | H |
| 1984 | I |
| 1985 | J |
| 1986 | K |
| 1987 | L |
| 1988 | M |
| 1989 | N |
| 1990 | O |
| 1991 | P |
| 1992 | Q |
| 1993 | R |
| 1994 | S |
| 1995 | T |
| 1996 | V |
| 1997 | Z |
| 1998 | U |
| 1999 | X |
| 2000 | AB |
| 2001 | DE |
| 2002 | DT |
| 2003 | AD |
| 2004 | CL |
| 2005 | MA |
| 2006 | OP |
| 2007 | EO |
| 2008 | PJ |
| 2009 | LT |
| 2010 | RS |
| 2011 | CX |