diff --git a/src/errors/Messages.js b/src/errors/Messages.js
index 980bf0975f27..4e9d73cacbd2 100644
--- a/src/errors/Messages.js
+++ b/src/errors/Messages.js
@@ -13,7 +13,7 @@ const Messages = {
   WS_CONNECTION_EXISTS: 'There is already an existing WebSocket connection.',
   WS_NOT_OPEN: (data = 'data') => `Websocket not open to send ${data}`,
 
-  BITFIELD_INVALID: 'Invalid bitfield flag or number.',
+  BITFIELD_INVALID: bit => `Invalid bitfield flag or number: ${bit}.`,
 
   SHARDING_INVALID: 'Invalid shard settings were provided.',
   SHARDING_REQUIRED: 'This session would have handled too many guilds - Sharding is required.',
diff --git a/src/util/BitField.js b/src/util/BitField.js
index 4d03aa6a5b11..fabbaf918f50 100644
--- a/src/util/BitField.js
+++ b/src/util/BitField.js
@@ -147,9 +147,7 @@ class BitField {
     if (bit instanceof BitField) return bit.bitfield;
     if (Array.isArray(bit)) return bit.map(p => this.resolve(p)).reduce((prev, p) => prev | p, 0);
     if (typeof bit === 'string' && typeof this.FLAGS[bit] !== 'undefined') return this.FLAGS[bit];
-    const error = new RangeError('BITFIELD_INVALID');
-    error.bit = bit;
-    throw error;
+    throw new RangeError('BITFIELD_INVALID', bit);
   }
 }