diff --git a/Library/Homebrew/tap_auditor.rb b/Library/Homebrew/tap_auditor.rb
index 7a5063546c5fa..2211b9a71307a 100644
--- a/Library/Homebrew/tap_auditor.rb
+++ b/Library/Homebrew/tap_auditor.rb
@@ -4,7 +4,7 @@
 module Homebrew
   # Auditor for checking common violations in {Tap}s.
   class TapAuditor
-    attr_reader :name, :path, :formula_names, :formula_aliases, :formula_renames, :cask_tokens,
+    attr_reader :name, :path, :formula_names, :formula_aliases, :formula_renames, :cask_tokens, :cask_renames,
                 :tap_audit_exceptions, :tap_style_exceptions, :problems
 
     sig { params(tap: Tap, strict: T.nilable(T::Boolean)).void }
@@ -27,6 +27,7 @@ def initialize(tap, strict:)
           formula_alias.split("/").last
         end
         @formula_renames = tap.formula_renames
+        @cask_renames = tap.cask_renames
         @formula_names = tap.formula_names.map do |formula_name|
           formula_name.split("/").last
         end
@@ -54,7 +55,8 @@ def audit_json_files
     def audit_tap_formula_lists
       check_formula_list_directory "audit_exceptions", @tap_audit_exceptions
       check_formula_list_directory "style_exceptions", @tap_style_exceptions
-      check_formula_list "formula_renames", @formula_renames.values
+      check_renames "formula_renames.json", @formula_renames, @formula_names, @formula_aliases
+      check_renames "cask_renames.json", @cask_renames, @cask_tokens
       check_formula_list ".github/autobump.txt", @tap_autobump unless @tap_official
       check_formula_list "synced_versions_formulae", @tap_synced_versions_formulae.flatten
     end
@@ -107,5 +109,78 @@ def check_formula_list_directory(directory_name, lists)
         check_formula_list "#{directory_name}/#{list_name}", list
       end
     end
+
+    sig {
+      params(list_file: String, renames_hash: T::Hash[String, String], valid_tokens: T::Array[String],
+             valid_aliases: T::Array[String]).void
+    }
+    def check_renames(list_file, renames_hash, valid_tokens, valid_aliases = [])
+      item_type = list_file.include?("cask") ? "casks" : "formulae"
+
+      # Collect all validation issues in a single pass
+      invalid_format_entries = []
+      invalid_targets = []
+      chained_rename_suggestions = []
+      conflicts = []
+
+      renames_hash.each do |old_name, new_name|
+        # Check for .rb extensions
+        if old_name.end_with?(".rb") || new_name.end_with?(".rb")
+          invalid_format_entries << "\"#{old_name}\": \"#{new_name}\""
+        end
+
+        # Check that new name exists
+        if valid_tokens.exclude?(new_name) && valid_aliases.exclude?(new_name) && !renames_hash.key?(new_name)
+          invalid_targets << new_name
+        end
+
+        # Check for chained renames and follow to final target
+        if renames_hash.key?(new_name)
+          final = new_name
+          seen = Set.new([old_name, new_name])
+          while renames_hash.key?(final)
+            next_name = renames_hash[final]
+            break if next_name.nil? || seen.include?(next_name)
+
+            final = next_name
+            seen << final
+          end
+          chained_rename_suggestions << "  \"#{old_name}\": \"#{final}\" (instead of chained rename)"
+        end
+
+        # Check for conflicts
+        conflicts << old_name if valid_tokens.include?(old_name)
+      end
+
+      if invalid_format_entries.any?
+        problem <<~EOS
+          #{list_file} contains entries with '.rb' file extensions.
+          Rename entries should use formula/cask names only, without '.rb' extensions.
+          Invalid entries: #{invalid_format_entries.join(", ")}
+        EOS
+      end
+
+      if invalid_targets.any?
+        problem <<~EOS
+          #{list_file} contains renames to #{item_type} that do not exist in the #{@name} tap.
+          Invalid targets: #{invalid_targets.join(", ")}
+        EOS
+      end
+
+      if chained_rename_suggestions.any?
+        problem <<~EOS
+          #{list_file} contains chained renames that should be collapsed.
+          Chained renames don't work automatically; each old name should point directly to the final target:
+          #{chained_rename_suggestions.join("\n")}
+        EOS
+      end
+
+      return if conflicts.none?
+
+      problem <<~EOS
+        #{list_file} contains old names that conflict with existing #{item_type} in the #{@name} tap.
+        Renames only work after the old #{item_type} are deleted. Conflicting names: #{conflicts.join(", ")}
+      EOS
+    end
   end
 end
diff --git a/Library/Homebrew/test/tap_auditor_spec.rb b/Library/Homebrew/test/tap_auditor_spec.rb
new file mode 100644
index 0000000000000..0b45b339b2f0b
--- /dev/null
+++ b/Library/Homebrew/test/tap_auditor_spec.rb
@@ -0,0 +1,300 @@
+# frozen_string_literal: true
+
+require "tap_auditor"
+
+RSpec.describe Homebrew::TapAuditor do
+  let(:tap) { Tap.fetch("homebrew", "foo") }
+  let(:tap_path) { tap.path }
+  let(:auditor) { described_class.new(tap, strict: false) }
+
+  def write_cask(token, path = tap_path/"Casks"/"#{token}.rb")
+    path.dirname.mkpath
+    path.write <<~RUBY
+      cask "#{token}" do
+        version "1.0"
+        url "https://brew.sh/#{token}-1.0.dmg"
+        name "#{token.capitalize} Cask"
+        homepage "https://brew.sh"
+      end
+    RUBY
+  end
+
+  def write_formula(name, path = tap_path/"Formula"/"#{name}.rb")
+    path.dirname.mkpath
+    path.write <<~RUBY
+      class #{name.capitalize} < Formula
+        url "https://brew.sh/#{name}-1.0.tar.gz"
+        version "1.0"
+      end
+    RUBY
+  end
+
+  before do
+    tap_path.mkpath
+    tap.clear_cache
+  end
+
+  describe "#audit" do
+    subject(:problems) do
+      auditor.audit
+      auditor.problems
+    end
+
+    context "with cask_renames.json" do
+      let(:cask_renames_path) { tap_path/"cask_renames.json" }
+      let(:renames_data) { {} }
+
+      before do
+        cask_renames_path.write JSON.pretty_generate(renames_data)
+      end
+
+      context "when .rb extension in old cask name (key)" do
+        let(:renames_data) { { "oldcask.rb" => "newcask" } }
+
+        before do
+          write_cask("newcask")
+        end
+
+        it "detects the invalid format" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains entries with '.rb' file extensions.
+              Rename entries should use formula/cask names only, without '.rb' extensions.
+              Invalid entries: "oldcask.rb": "newcask"
+            EOS
+          )
+        end
+      end
+
+      context "when .rb extension in new cask name (value)" do
+        let(:renames_data) { { "oldcask" => "newcask.rb" } }
+
+        before do
+          write_cask("newcask")
+        end
+
+        it "detects the invalid format" do
+          expect(problems.count).to eq(2)
+
+          invalid_format_problem = problems.find do |p|
+            p[:message].include?("entries with '.rb' file extensions")
+          end
+          expect(invalid_format_problem[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains entries with '.rb' file extensions.
+              Rename entries should use formula/cask names only, without '.rb' extensions.
+              Invalid entries: "oldcask": "newcask.rb"
+            EOS
+          )
+
+          invalid_target_problem = problems.find do |p|
+            p[:message].include?("Invalid targets")
+          end
+          expect(invalid_target_problem[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains renames to casks that do not exist in the homebrew/foo tap.
+              Invalid targets: newcask.rb
+            EOS
+          )
+        end
+      end
+
+      context "when missing target cask" do
+        let(:renames_data) { { "oldcask" => "nonexistent" } }
+
+        it "detects the missing target" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains renames to casks that do not exist in the homebrew/foo tap.
+              Invalid targets: nonexistent
+            EOS
+          )
+        end
+      end
+
+      context "with chained renames" do
+        let(:renames_data) do
+          {
+            "oldcask" => "newcask",
+            "newcask" => "finalcask",
+          }
+        end
+
+        before do
+          write_cask("finalcask")
+        end
+
+        it "detects the chained renames" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains chained renames that should be collapsed.
+              Chained renames don't work automatically; each old name should point directly to the final target:
+                "oldcask": "finalcask" (instead of chained rename)
+            EOS
+          )
+        end
+      end
+
+      context "with multi-level chained renames" do
+        let(:renames_data) do
+          {
+            "oldcask"          => "newcask",
+            "newcask"          => "intermediatecask",
+            "intermediatecask" => "finalcask",
+          }
+        end
+
+        before do
+          write_cask("intermediatecask")
+          write_cask("finalcask")
+        end
+
+        it "suggests final target" do
+          expect(problems.count).to eq(2)
+
+          chained_problem = problems.find { |p| p[:message].include?("chained renames") }
+          expect(chained_problem[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains chained renames that should be collapsed.
+              Chained renames don't work automatically; each old name should point directly to the final target:
+                "oldcask": "finalcask" (instead of chained rename)
+                "newcask": "finalcask" (instead of chained rename)
+            EOS
+          )
+
+          conflict_problem = problems.find { |p| p[:message].include?("conflict") }
+          expect(conflict_problem[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains old names that conflict with existing casks in the homebrew/foo tap.
+              Renames only work after the old casks are deleted. Conflicting names: intermediatecask
+            EOS
+          )
+        end
+      end
+
+      context "with chained renames where intermediates don't exist" do
+        let(:renames_data) do
+          {
+            "veryoldcask"      => "intermediatecask",
+            "intermediatecask" => "finalcask",
+          }
+        end
+
+        before do
+          write_cask("finalcask")
+        end
+
+        it "reports chained rename error, not invalid target error" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains chained renames that should be collapsed.
+              Chained renames don't work automatically; each old name should point directly to the final target:
+                "veryoldcask": "finalcask" (instead of chained rename)
+            EOS
+          )
+        end
+      end
+
+      context "when old name conflicts with existing cask" do
+        let(:renames_data) { { "newcask" => "anothercask" } }
+
+        before do
+          write_cask("newcask")
+          write_cask("anothercask")
+        end
+
+        it "detects the conflict" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              cask_renames.json contains old names that conflict with existing casks in the homebrew/foo tap.
+              Renames only work after the old casks are deleted. Conflicting names: newcask
+            EOS
+          )
+        end
+      end
+
+      context "with correct rename entries" do
+        let(:renames_data) { { "oldcask" => "newcask" } }
+
+        before do
+          write_cask("newcask")
+        end
+
+        it "passes validation" do
+          rename_problems = problems.select { |p| p[:message].include?("cask_renames") }
+          expect(rename_problems).to be_empty
+        end
+      end
+    end
+
+    context "with formula_renames.json" do
+      let(:formula_renames_path) { tap_path/"formula_renames.json" }
+      let(:renames_data) { {} }
+
+      before do
+        formula_renames_path.write JSON.pretty_generate(renames_data)
+      end
+
+      context "when .rb extension in formula rename keys" do
+        let(:renames_data) { { "oldformula.rb" => "newformula" } }
+
+        before do
+          write_formula("newformula")
+        end
+
+        it "detects the invalid format" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              formula_renames.json contains entries with '.rb' file extensions.
+              Rename entries should use formula/cask names only, without '.rb' extensions.
+              Invalid entries: "oldformula.rb": "newformula"
+            EOS
+          )
+        end
+      end
+
+      context "with chained formula renames" do
+        let(:renames_data) do
+          {
+            "oldformula" => "newformula",
+            "newformula" => "finalformula",
+          }
+        end
+
+        before do
+          write_formula("finalformula")
+        end
+
+        it "detects the chained renames" do
+          expect(problems.count).to eq(1)
+          expect(problems.first[:message]).to eq(
+            <<~EOS,
+              formula_renames.json contains chained renames that should be collapsed.
+              Chained renames don't work automatically; each old name should point directly to the final target:
+                "oldformula": "finalformula" (instead of chained rename)
+            EOS
+          )
+        end
+      end
+
+      context "with correct formula rename entries" do
+        let(:renames_data) { { "oldformula" => "newformula" } }
+
+        before do
+          write_formula("newformula")
+        end
+
+        it "passes validation" do
+          rename_problems = problems.select { |p| p[:message].include?("formula_renames") }
+          expect(rename_problems).to be_empty
+        end
+      end
+    end
+  end
+end
diff --git a/docs/Rename-A-Formula.md b/docs/Rename-A-Formula.md
index 4c7089565a11a..bac3595f3184d 100644
--- a/docs/Rename-A-Formula.md
+++ b/docs/Rename-A-Formula.md
@@ -2,7 +2,9 @@
 last_review_date: "1970-01-01"
 ---
 
-# Renaming a Formula
+# Renaming a Formula or Cask
+
+## Renaming a Formula
 
 Sometimes software and formulae need to be renamed. To rename a formula you need to:
 
@@ -17,3 +19,18 @@ A `formula_renames.json` example for a formula rename:
   "ack": "newack"
 }
 ```
+
+## Renaming a Cask
+
+To rename a cask, follow a similar process:
+
+1. Rename the cask file and update the cask stanza to use the new cask token. The new token must meet all the usual rules of cask naming.
+2. Create a pull request on the corresponding tap deleting the old cask file, adding the new cask file, and adding it to `cask_renames.json` with a commit message like `new-token: renamed from old-token`.
+
+A `cask_renames.json` example:
+
+```json
+{
+  "old-token": "new-token"
+}
+```