diff --git a/ports/bsd/bip-init.c b/ports/bsd/bip-init.c
index f6df2989..d0b17bfe 100644
--- a/ports/bsd/bip-init.c
+++ b/ports/bsd/bip-init.c
@@ -763,6 +763,9 @@ void bip_cleanup(void)
         close(BIP_Broadcast_Socket);
     }
     BIP_Broadcast_Socket = -1;
+    /* these were set non-zero during interface configuration */
+    BIP_Address.s_addr = 0;
+    BIP_Broadcast_Addr.s_addr = 0;
 
     return;
 }
diff --git a/ports/linux/bip-init.c b/ports/linux/bip-init.c
index 65ae1a4a..182112f5 100644
--- a/ports/linux/bip-init.c
+++ b/ports/linux/bip-init.c
@@ -955,6 +955,9 @@ void bip_cleanup(void)
         close(BIP_Broadcast_Socket);
     }
     BIP_Broadcast_Socket = -1;
+    /* these were set non-zero during interface configuration */
+    BIP_Address.s_addr = 0;
+    BIP_Broadcast_Addr.s_addr = 0;
 
     return;
 }
diff --git a/ports/win32/bip-init.c b/ports/win32/bip-init.c
index 8c7b5c22..9b4c8d92 100644
--- a/ports/win32/bip-init.c
+++ b/ports/win32/bip-init.c
@@ -920,6 +920,9 @@ void bip_cleanup(void)
         BIP_Initialized = false;
         WSACleanup();
     }
+    /* these were set non-zero during interface configuration */
+    BIP_Address.s_addr = 0;
+    BIP_Broadcast_Addr.s_addr = 0;
 
     return;
 }