diff --git a/Shorewall/Perl/Shorewall/Providers.pm b/Shorewall/Perl/Shorewall/Providers.pm
index ea510826c..31407c096 100644
--- a/Shorewall/Perl/Shorewall/Providers.pm
+++ b/Shorewall/Perl/Shorewall/Providers.pm
@@ -349,6 +349,8 @@ sub add_a_provider( ) {
 	}
     }
 
+    fatal_error q(The 'balance' and 'fallback' options are mutually exclusive) if $balance && $default;
+
     my $val = 0;
     my $pref;
 
diff --git a/Shorewall/changelog.txt b/Shorewall/changelog.txt
index b41b6ef2b..e2cdf6f7f 100644
--- a/Shorewall/changelog.txt
+++ b/Shorewall/changelog.txt
@@ -2,6 +2,8 @@ Changes in Shorewall 4.4.21 Final
 
 1) Correct code generated by TPROXY.
 
+2) Make 'fallback' and 'balance' mutually exclusive.
+
 Changes in Shorewall 4.4.21 RC 1
 
 1)  Fix empty parameter lists in _DEFAULT settings.
diff --git a/Shorewall/releasenotes.txt b/Shorewall/releasenotes.txt
index 7616b2ed5..52c685b79 100644
--- a/Shorewall/releasenotes.txt
+++ b/Shorewall/releasenotes.txt
@@ -38,6 +38,10 @@ VI.   PROBLEMS CORRECTED AND NEW FEATURES IN PRIOR RELEASES
           ERROR: iptables-restore Failed. Input is in
 	  	 /var/lib/shorewall/.iptables-restore-input
 
+4)  The 'balance' and 'fallback' options in /etc/shorewall/providers
+    have always been mutually exclusive but the compiler previously
+    didn't enforce that restriction. Now it does.
+
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