diff --git a/spec/controllers/settings/theme_controller_spec.rb b/spec/controllers/settings/theme_controller_spec.rb
new file mode 100644
index 00000000..b573fb78
--- /dev/null
+++ b/spec/controllers/settings/theme_controller_spec.rb
@@ -0,0 +1,83 @@
+# frozen_string_literal: true
+
+require "rails_helper"
+
+describe Settings::ThemeController, type: :controller do
+  describe "#edit" do
+    subject { get :edit }
+
+    context "user signed in" do
+      let(:user) { FactoryBot.create(:user) }
+
+      before { sign_in user }
+
+      it "renders the edit template" do
+        subject
+        expect(response).to render_template(:edit)
+      end
+    end
+  end
+
+  describe "#update" do
+    let(:user) { FactoryBot.create(:user) }
+
+    let(:update_attributes) do 
+      { 
+        theme: {
+          primary_color: 6174129,
+          primary_text: 16777215,
+          danger_color: 14431557,
+          danger_text: 16777215,
+          success_color: 2664261,
+          success_text: 16777215,
+          warning_color: 16761095,
+          warning_text: 2697513,
+          info_color: 1548984,
+          info_text: 16777215,
+          dark_color: 3422784,
+          dark_text: 15658734,
+          light_color: 16316922,
+          light_text: 0,
+          raised_background: 16777215,
+          raised_accent: 16250871,
+          background_color: 15789556,
+          body_text: 0,
+          muted_text: 7107965,
+          input_color: 15789556,
+          input_text: 0
+        } 
+      }
+    end
+
+    subject { patch :update, params: update_attributes }
+
+    context "user signed in" do
+      before { sign_in user }
+
+      context "user has no theme" do
+        it "creates a new theme" do
+          expect { subject }.to change { user.reload.theme }
+        end
+
+        it "renders the edit template" do
+          subject
+          expect(response).to redirect_to(:edit_user_theme)
+        end
+      end
+
+      context "user has a theme" do
+        let(:user) { FactoryBot.create(:user) }
+        let(:theme) { FactoryBot.create(:theme, user: user) }
+
+        it "updates the theme" do
+          expect { subject }.to change { theme.reload.attributes }
+        end
+
+        it "renders the edit template" do
+          subject
+          expect(response).to redirect_to(:edit_user_theme)
+        end
+      end
+    end
+  end
+end