PHB + homebrew

Sending

3-level Evocation

You send a short message of twenty-five words or less to a creature with which you are familiar. The creature hears the message in its mind, recognizes you as the sender if it knows you, and can answer in a like manner immediately. The spell enables creatures with Intelligence scores of at least 1 to understand the meaning of your message.
You can send the message across any distance and even to other planes of existence, but if the target is on a different plane than you, there is a 95% percent chance that the message doesn't arrive.
At higher levels: When cast at higher levels the message increases by 10 words for each level above 3rd.