diff --git a/doc/release-notes.md b/doc/release-notes.md
index 46dd795eb60..19f77b94efc 100644
--- a/doc/release-notes.md
+++ b/doc/release-notes.md
@@ -48,6 +48,11 @@ known problems when downgrading from 0.11.x to 0.10.x.
 Notable changes since 0.11.2
 ============================
 
+Alert system
+--------------
+
+The P2P alert system is off by default. To turn on, use `-alert` with startup
+configuration.
 
 0.11.3 Change log
 =================
diff --git a/src/main.h b/src/main.h
index 74911f6e659..7f2e3fb4e25 100644
--- a/src/main.h
+++ b/src/main.h
@@ -53,7 +53,7 @@ static const unsigned int DEFAULT_BLOCK_MIN_SIZE = 0;
 /** Default for -blockprioritysize, maximum space for zero/low-fee transactions **/
 static const unsigned int DEFAULT_BLOCK_PRIORITY_SIZE = 50000;
 /** Default for accepting alerts from the P2P network. */
-static const bool DEFAULT_ALERTS = true;
+static const bool DEFAULT_ALERTS = false;
 /** The maximum size for transactions we're willing to relay/mine */
 static const unsigned int MAX_STANDARD_TX_SIZE = 100000;
 /** Maximum number of signature check operations in an IsStandard() P2SH script */