Does Islam sanction such behavior? Can it regard such behavior as a harmless custom? Can we concoct lies containing happy or sad news, as long as we quickly inform the other person that it is a lie or cry out “April Fools!”?
Lying is not permissible at all, at any time. And it is not permissible to imitate the kuffar (non-Muslims) and to be like them, on this day or on any other, because the Prophet (peace and blessings of Allah be upon him) said: “Whoever imitates a people is one of them.”
To start with, we must know that a lie is defined as giving information about something, where that information is at variance with the truth. A lie is forbidden in Islam.
The Prophet (peace be upon him) said: “Be truthful, for indeed truth guides us to righteousness, and righteousness leads us to Paradise. A man remains honest and steadfast in ascertaining the truth until he is recorded with Allah as a truthful person. A lie guides us to wickedness, and wickedness leads us to Hell. A man keeps lying and seeking out lies until he is recorded with Allah as a liar.” [Sahîh al-Bukhârî (6134) and Sahîh Muslim (2607)]