A green tick indicates that a user logged onto the Elite Singles in the last 24 hours. It suggests that this user is actively searching for matches or at least replying to messages.

What does a green check mark mean on Eharmony?

You can see the status of the messages youve sent in your profile under the Messages section. If you have sent a message, the check marks indicate the status: If one of the two checks is green, this means that your contact has received the message. If both checks are green, your contact has read the message.