diff --git a/src/channels/irc.rs b/src/channels/irc.rs
index d53ca25..d63ad41 100644
--- a/src/channels/irc.rs
+++ b/src/channels/irc.rs
@@ -453,13 +453,22 @@ impl Channel for IrcChannel {
                 "AUTHENTICATE" => {
                     // Server sends "AUTHENTICATE +" to request credentials
                     if sasl_pending && msg.params.first().is_some_and(|p| p == "+") {
-                        let encoded = encode_sasl_plain(
-                            &current_nick,
-                            self.sasl_password.as_deref().unwrap_or(""),
-                        );
-                        let mut guard = self.writer.lock().await;
-                        if let Some(ref mut w) = *guard {
-                            Self::send_raw(w, &format!("AUTHENTICATE {encoded}")).await?;
+                        if let Some(password) = self.sasl_password.as_deref() {
+                            let encoded = encode_sasl_plain(&current_nick, password);
+                            let mut guard = self.writer.lock().await;
+                            if let Some(ref mut w) = *guard {
+                                Self::send_raw(w, &format!("AUTHENTICATE {encoded}")).await?;
+                            }
+                        } else {
+                            // SASL was requested but no password is configured; abort SASL
+                            tracing::warn!(
+                                "SASL authentication requested but no SASL password is configured; aborting SASL"
+                            );
+                            sasl_pending = false;
+                            let mut guard = self.writer.lock().await;
+                            if let Some(ref mut w) = *guard {
+                                Self::send_raw(w, "CAP END").await?;
+                            }
                         }
                     }
                 }