diff --git a/app/mailers/request_mailer.rb b/app/mailers/request_mailer.rb
index 814916a1e8..570b77c08d 100644
--- a/app/mailers/request_mailer.rb
+++ b/app/mailers/request_mailer.rb
@@ -16,8 +16,10 @@ def request_cancel_partner_notification(request_id:)
     end
     @formatted_requested_items.sort_by! { |rt| rt[:name] }
 
+    recipients = [@partner.email, @request.requester.email].uniq
+
     mail(
-      to: @partner.email,
+      to: recipients,
       subject: "Your essentials request (##{@request.id}) has been canceled."
     )
   end
diff --git a/app/models/request.rb b/app/models/request.rb
index 6c4590975b..0e9efa673a 100644
--- a/app/models/request.rb
+++ b/app/models/request.rb
@@ -59,8 +59,10 @@ def total_items
   end
 
   def requester
-    # Despite the field being called "partner_user_id", it can refer to both a partner user or an organization admin
-    partner_user_id ? partner_user : partner
+    # Despite the field being called "partner_user_id", it can refer to both a partner user or an organization admin.
+    # Keyed off the association rather than the id: User is default-scoped to kept records, so a discarded
+    # user leaves partner_user_id set while partner_user resolves to nil.
+    partner_user || partner
   end
 
   def request_type_label
diff --git a/spec/mailers/request_mailer_spec.rb b/spec/mailers/request_mailer_spec.rb
index 4ea835077e..9e203a1bf8 100644
--- a/spec/mailers/request_mailer_spec.rb
+++ b/spec/mailers/request_mailer_spec.rb
@@ -1,22 +1,47 @@
 RSpec.describe RequestMailer, type: :mailer do
   describe "#request_cancel_partner_notification" do
     subject { described_class.request_cancel_partner_notification(request_id: request.id) }
-    let(:request) { create(:request) }
-
-    it "renders the body with correct text with partner information" do
-      html = html_body(subject)
-      expect(html).to include("Hello there, <strong>#{request.partner.name}</strong>")
-      expect(html).to include("One of your essentials requests (##{request.id}) have been canceled.")
-      text = text_body(subject)
-      expect(text).to include("Hello there, #{request.partner.name}")
-      expect(text).to include("One of your essentials requests (##{request.id}) have been canceled.")
+
+    let(:partner) { create(:partner, email: "partner@example.com") }
+
+    context "when the request was sent by a partner user" do
+      let(:partner_user) { create(:partner_user, email: "requester@example.com", partner: partner) }
+      let(:request) { create(:request, partner: partner, partner_user: partner_user) }
+
+      it "renders the body with correct text with partner information" do
+        html = html_body(subject)
+        expect(html).to include("Hello there, <strong>#{request.partner.name}</strong>")
+        expect(html).to include("One of your essentials requests (##{request.id}) have been canceled.")
+        text = text_body(subject)
+        expect(text).to include("Hello there, #{request.partner.name}")
+        expect(text).to include("One of your essentials requests (##{request.id}) have been canceled.")
+      end
+
+      it "is sent to both the partner and the request sender with the correct subject line" do
+        expect(subject.to).to match_array(["partner@example.com", "requester@example.com"])
+        expect(subject.from).to eq(['no-reply@humanessentials.app'])
+        expect(subject.subject).to eq("Your essentials request (##{request.id}) has been canceled.")
+      end
+    end
+
+    context "when the request has no partner user" do
+      let(:request) { create(:request, partner: partner, partner_user: nil) }
+
+      it "is sent only to the partner main email" do
+        expect(subject.to).to eq(["partner@example.com"])
+      end
     end
 
-    it "should be sent to the partner main email with the correct subject line" do
-      expect(subject.to).to eq([request.partner.email])
-      expect(subject.from).to eq(['no-reply@humanessentials.app'])
-      expect(subject.subject).to eq("Your essentials request (##{request.id}) has been canceled.")
+    context "when the partner user who sent the request has since been discarded" do
+      let(:partner_user) { create(:partner_user, email: "requester@example.com", partner: partner) }
+      let(:request) { create(:request, partner: partner, partner_user: partner_user) }
+
+      it "is still sent to the partner main email" do
+        request
+        partner_user.discard
+
+        expect(subject.to).to eq(["partner@example.com"])
+      end
     end
   end
 end
-
diff --git a/spec/models/request_spec.rb b/spec/models/request_spec.rb
index e203179deb..247bd7ec57 100644
--- a/spec/models/request_spec.rb
+++ b/spec/models/request_spec.rb
@@ -177,6 +177,38 @@
     end
   end
 
+  describe "requester" do
+    let(:partner) { create(:partner) }
+
+    context "when a partner user submitted the request" do
+      let(:partner_user) { create(:partner_user, partner: partner) }
+
+      it "returns the partner user" do
+        request = create(:request, partner: partner, partner_user: partner_user)
+        expect(request.requester).to eq(partner_user)
+      end
+    end
+
+    context "when no partner user is recorded" do
+      it "returns the partner" do
+        request = create(:request, partner: partner, partner_user: nil)
+        expect(request.requester).to eq(partner)
+      end
+    end
+
+    context "when the partner user has since been discarded" do
+      let(:partner_user) { create(:partner_user, partner: partner) }
+
+      it "falls back to the partner" do
+        request = create(:request, partner: partner, partner_user: partner_user)
+        partner_user.discard
+
+        expect(request.reload.partner_user_id).to eq(partner_user.id)
+        expect(request.requester).to eq(partner)
+      end
+    end
+  end
+
   describe "versioning" do
     it { is_expected.to be_versioned }
   end