The secret code for "I miss you" is 607.
This "code" appears to be a short, numerical representation of the phrase "I miss you," possibly used in a specific context or as a personal code between individuals. It gained some recognition on September 18, 2012. While not a widely known or standardized code, its meaning is directly linked to the sentiment of missing someone.
It's important to note that "secret codes" can be anything agreed upon by the involved parties. Therefore, 607 is a secret code for "I miss you," but not necessarily the universal secret code. Other codes could exist depending on the context.