There is no definite time limit for sending sympathy cards, and therefore it can never be too late to send one. However, it is a good idea to send a sympathy card within 2 weeks of hearing the bad news, according to the Gallery Collection.
Sending a sympathy card is a nice gesture and a show of concern for the people most affected. While it may seem rude to send the card after 2 weeks, many reasons may lead to this outcome, such as an individual not finding out about the news until a month later or not knowing what to write at the time. As long as the card contains a heartfelt message, sending it can never be too late, suggests the Gallery Collection