diff --git a/includes/exceptions/exceptions.hpp b/includes/exceptions/exceptions.hpp
index 77ac7e1..dde57d4 100644
--- a/includes/exceptions/exceptions.hpp
+++ b/includes/exceptions/exceptions.hpp
@@ -14,7 +14,6 @@
 # define ERR_NO_NICKNAME_GIVEN ":No nickname given"
 # define ERR_ERRONEUS_NICKNAME(nick)  (nick) + " :Erroneus nickname"
 # define ERR_NICKNAME_IN_USE(nick) (nick) + " :Nickname is already in use"
-# define ERR_NICK_COLLISION(nick) (nick) + " :Nickname collision KILL"
 # define ERR_PASSWD_MISMATCH ":Password incorrect"
 
 # define ERR_INVITE_ONLY_CHAN(channel) (channel) + " :Cannot join channel (+i)"
@@ -72,14 +71,6 @@ class NeedMoreParamsException : public IRCException {
         NeedMoreParamsException(const std::string &command) : IRCException("461", ERR_NEED_MORE_PARAMS(command)) {}
 };
 
-/**
- * This exception is thrown when a nickname is already in use. (Nickname collision)
- * It is thrown when a user tries to set a nickname the first time, and it is already in use.
- */
-class NickCollisionException : public IRCException {
-    public:
-        NickCollisionException(const std::string &nickname) : IRCException("436", ERR_NICK_COLLISION(nickname)) {}
-};
 
 /**
  * This exception is thrown when a nickname is already in use.
diff --git a/src/commands/NickCommand.cpp b/src/commands/NickCommand.cpp
index 4820fb7..e648234 100644
--- a/src/commands/NickCommand.cpp
+++ b/src/commands/NickCommand.cpp
@@ -24,7 +24,6 @@ NickCommand::~NickCommand() {}
  * 
  * @throws `NoNicknameGivenException` If the nickname is empty
  * @throws `ErroneousNicknameException` If the nickname is too long or invalid
- * @throws `NickCollisionException` If the nickname is already in use and the user is not registered
  * @throws `NicknameInUseException` If the nickname is already in use and the user is registered
  * 
  */
@@ -39,9 +38,7 @@ void NickCommand::execute(int clientFd) {
     User &user = server.getUserByFd(clientFd);
 
     if (server.isNicknameInUse(this->_nickname))
-        user.isRegistered()
-            ? throw NicknameInUseException(this->_nickname)
-            : throw NickCollisionException(this->_nickname);
+        throw NicknameInUseException(this->_nickname);
 
     if (!NickCommand::isValidNickname())
         throw ErroneousNicknameException(this->_nickname);