diff --git a/Library/Homebrew/formula_auditor.rb b/Library/Homebrew/formula_auditor.rb
index a45d7166f4..55c6d0976f 100644
--- a/Library/Homebrew/formula_auditor.rb
+++ b/Library/Homebrew/formula_auditor.rb
@@ -318,9 +318,24 @@ module Homebrew
         conflicting_formula = Formulary.factory(c.name)
         problem "Formula should not conflict with itself" if formula == conflicting_formula
 
-        # Use Formula instead of FormulaConflict to be able correctly handle renamed formulae and aliases
-        reverse_conflicts = conflicting_formula.conflicts.map { |rc| Formulary.factory(rc.name) }
-        if reverse_conflicts.exclude? formula
+        next unless @core_tap
+
+        if CoreTap.instance.formula_renames.key?(c.name) || Formula.aliases.include?(c.name)
+          problem "Formula conflict should be declared using " \
+                  "canonical name (#{conflicting_formula.name}) instead of #{c.name}"
+        end
+
+        rev_conflict_found = false
+        conflicting_formula.conflicts.each do |rc|
+          rc_formula = Formulary.factory(rc.name)
+          if CoreTap.instance.formula_renames.key?(rc.name) || Formula.aliases.include?(rc.name)
+            problem "Formula #{conflicting_formula.name} conflict should be declared using " \
+                    "canonical name (#{rc_formula.name}) instead of #{rc.name}"
+          end
+
+          rev_conflict_found ||= rc_formula == formula
+        end
+        unless rev_conflict_found
           problem "Formula #{conflicting_formula.name} should also have a conflict declared with #{formula.name}"
         end
       rescue TapFormulaUnavailableError
diff --git a/Library/Homebrew/test/dev-cmd/audit_spec.rb b/Library/Homebrew/test/dev-cmd/audit_spec.rb
index 259e6bd2c1..d9040f4055 100644
--- a/Library/Homebrew/test/dev-cmd/audit_spec.rb
+++ b/Library/Homebrew/test/dev-cmd/audit_spec.rb
@@ -1142,7 +1142,7 @@ module Homebrew
 
     describe "#audit_conflicts" do
       specify "it warns when conflicting with non-existing formula" do
-        fa = formula_auditor "foo", <<~RUBY
+        fa = formula_auditor "foo", <<~RUBY, core_tap: true
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"
 
@@ -1157,7 +1157,7 @@ module Homebrew
       end
 
       specify "it warns when conflicting with itself" do
-        fa = formula_auditor "foo", <<~RUBY
+        fa = formula_auditor "foo", <<~RUBY, core_tap: true
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"
 
@@ -1172,13 +1172,13 @@ module Homebrew
       end
 
       specify "it warns when another formula does not have a symmetric conflict" do
-        formula_auditor "bar", <<~RUBY
+        formula_auditor "bar", <<~RUBY, core_tap: true
           class Bar < Formula
             url "https://brew.sh/foo-1.0.tgz"
           end
         RUBY
 
-        fa = formula_auditor "foo", <<~RUBY
+        fa = formula_auditor "foo", <<~RUBY, core_tap: true
           class Foo < Formula
             url "https://brew.sh/foo-1.0.tgz"