diff --git a/app/controllers/concerns/idv/document_capture_concern.rb b/app/controllers/concerns/idv/document_capture_concern.rb
index 9a32b78e67c..58038bda659 100644
--- a/app/controllers/concerns/idv/document_capture_concern.rb
+++ b/app/controllers/concerns/idv/document_capture_concern.rb
@@ -39,11 +39,9 @@ def extract_pii_from_doc(user, response, store_in_session: false)
         uuid_prefix: ServiceProvider.find_by(issuer: sp_session[:issuer])&.app_id,
       )
 
-      if defined?(flow_session) && defined?(idv_session) # hybrid mobile does not have idv_session
+      if defined?(idv_session) # hybrid mobile does not have idv_session
         idv_session.had_barcode_read_failure = response.attention_with_barcode?
         if store_in_session
-          flow_session[:pii_from_doc] ||= {}
-          flow_session[:pii_from_doc].merge!(pii_from_doc)
           idv_session.pii_from_doc ||= {}
           idv_session.pii_from_doc.merge!(pii_from_doc)
           idv_session.clear_applicant!
diff --git a/app/controllers/concerns/idv/verify_info_concern.rb b/app/controllers/concerns/idv/verify_info_concern.rb
index 65b0d22f722..03b3dde0be9 100644
--- a/app/controllers/concerns/idv/verify_info_concern.rb
+++ b/app/controllers/concerns/idv/verify_info_concern.rb
@@ -319,9 +319,10 @@ def move_applicant_to_idv_session
     end
 
     def delete_pii
-      flow_session.delete(:pii_from_doc)
       idv_session.pii_from_doc = nil
-      flow_session.delete(:pii_from_user)
+      if defined?(flow_session) # no longer defined for remote flow
+        flow_session.delete(:pii_from_user)
+      end
     end
 
     def add_proofing_costs(results)
diff --git a/app/controllers/concerns/idv_session.rb b/app/controllers/concerns/idv_session.rb
index 81658a78fca..741b547444f 100644
--- a/app/controllers/concerns/idv_session.rb
+++ b/app/controllers/concerns/idv_session.rb
@@ -32,10 +32,6 @@ def idv_session
     )
   end
 
-  def flow_session
-    user_session['idv/doc_auth'] ||= {}
-  end
-
   def irs_reproofing?
     current_user&.reproof_for_irs?(
       service_provider: current_sp,
diff --git a/app/controllers/concerns/idv_step_concern.rb b/app/controllers/concerns/idv_step_concern.rb
index cb5c27aca04..a2a9f9695e0 100644
--- a/app/controllers/concerns/idv_step_concern.rb
+++ b/app/controllers/concerns/idv_step_concern.rb
@@ -37,10 +37,6 @@ def redirect_for_mail_only
     redirect_to idv_mail_only_warning_url
   end
 
-  def pii_from_doc
-    idv_session.pii_from_doc || flow_session[:pii_from_doc]
-  end
-
   def pii_from_user
     flow_session['pii_from_user']
   end
@@ -57,7 +53,7 @@ def confirm_ssn_step_complete
   end
 
   def confirm_document_capture_complete
-    return if pii_from_doc.present?
+    return if idv_session.pii_from_doc.present?
 
     if flow_path == 'standard'
       redirect_to idv_document_capture_url
diff --git a/app/controllers/idv/address_controller.rb b/app/controllers/idv/address_controller.rb
index a877101c9e4..6c7fcf03d9d 100644
--- a/app/controllers/idv/address_controller.rb
+++ b/app/controllers/idv/address_controller.rb
@@ -7,7 +7,7 @@ class AddressController < ApplicationController
     def new
       analytics.idv_address_visit
 
-      @presenter = AddressPresenter.new(pii: pii_from_doc)
+      @presenter = AddressPresenter.new(pii: idv_session.pii_from_doc)
     end
 
     def update
@@ -24,17 +24,13 @@ def update
     private
 
     def idv_form
-      Idv::AddressForm.new(pii_from_doc)
+      Idv::AddressForm.new(idv_session.pii_from_doc)
     end
 
     def success
-      # Make sure pii_from_doc is available in both places so we can
-      # update the address for both and keep them in sync
-      idv_session.pii_from_doc = pii_from_doc
       profile_params.each do |key, value|
         idv_session.pii_from_doc[key] = value
       end
-      flow_session[:pii_from_doc] = idv_session.pii_from_doc
       redirect_to idv_verify_info_url
     end
 
diff --git a/app/controllers/idv/document_capture_controller.rb b/app/controllers/idv/document_capture_controller.rb
index 1359b6483ca..2e4eb7c7879 100644
--- a/app/controllers/idv/document_capture_controller.rb
+++ b/app/controllers/idv/document_capture_controller.rb
@@ -57,7 +57,7 @@ def confirm_hybrid_handoff_complete
     def confirm_document_capture_needed
       return if idv_session.redo_document_capture
 
-      return if pii_from_doc.blank? && !idv_session.verify_info_step_complete?
+      return if idv_session.pii_from_doc.blank? && !idv_session.verify_info_step_complete?
 
       redirect_to idv_ssn_url
     end
diff --git a/app/controllers/idv/link_sent_controller.rb b/app/controllers/idv/link_sent_controller.rb
index 350d945d8a1..d0c239dea7e 100644
--- a/app/controllers/idv/link_sent_controller.rb
+++ b/app/controllers/idv/link_sent_controller.rb
@@ -48,7 +48,7 @@ def confirm_hybrid_handoff_complete
     def confirm_document_capture_needed
       return if idv_session.redo_document_capture
 
-      return if pii_from_doc.blank? && !idv_session.verify_info_step_complete?
+      return if idv_session.pii_from_doc.blank? && !idv_session.verify_info_step_complete?
 
       redirect_to idv_ssn_url
     end
diff --git a/app/controllers/idv/ssn_controller.rb b/app/controllers/idv/ssn_controller.rb
index f0e64000d91..f3b3084a203 100644
--- a/app/controllers/idv/ssn_controller.rb
+++ b/app/controllers/idv/ssn_controller.rb
@@ -57,7 +57,7 @@ def confirm_repeat_ssn
     end
 
     def next_url
-      if pii_from_doc[:state] == 'PR' && !updating_ssn?
+      if idv_session.pii_from_doc[:state] == 'PR' && !updating_ssn?
         idv_address_url
       else
         idv_verify_info_url
diff --git a/app/controllers/idv/verify_info_controller.rb b/app/controllers/idv/verify_info_controller.rb
index cd4f7e1c340..a892f63ccc2 100644
--- a/app/controllers/idv/verify_info_controller.rb
+++ b/app/controllers/idv/verify_info_controller.rb
@@ -56,7 +56,7 @@ def analytics_arguments
     end
 
     def pii
-      @pii = pii_from_doc
+      @pii = idv_session.pii_from_doc
     end
   end
 end
diff --git a/spec/controllers/concerns/rate_limit_concern_spec.rb b/spec/controllers/concerns/rate_limit_concern_spec.rb
index f8e3b8b29b7..f48ecaa4659 100644
--- a/spec/controllers/concerns/rate_limit_concern_spec.rb
+++ b/spec/controllers/concerns/rate_limit_concern_spec.rb
@@ -26,7 +26,6 @@ def update
     before(:each) do
       sign_in(user)
       allow(subject).to receive(:current_user).and_return(user)
-      allow(subject).to receive(:flow_session).and_return({})
       routes.draw do
         get 'show' => 'idv/step#show'
         put 'update' => 'idv/step#update'
diff --git a/spec/controllers/idv/address_controller_spec.rb b/spec/controllers/idv/address_controller_spec.rb
index ea6708b75d1..b9e135e03c1 100644
--- a/spec/controllers/idv/address_controller_spec.rb
+++ b/spec/controllers/idv/address_controller_spec.rb
@@ -5,21 +5,14 @@
 
   let(:user) { create(:user) }
 
-  let(:idv_session) { subject.idv_session }
-
   let(:pii_from_doc) { Idp::Constants::MOCK_IDV_APPLICANT_WITH_SSN.stringify_keys }
 
-  let(:flow_session) do
-    { pii_from_doc: pii_from_doc }
-  end
-
   before do
     stub_sign_in(user)
     stub_analytics
     stub_idv_steps_before_verify_step(user)
     subject.idv_session.flow_path = 'standard'
     subject.idv_session.pii_from_doc = pii_from_doc
-    subject.user_session['idv/doc_auth'] = flow_session
   end
 
   describe '#new' do
@@ -53,31 +46,13 @@
     it 'sets address_edited in idv_session' do
       expect do
         put :update, params: params
-      end.to change { idv_session.address_edited }.from(nil).to eql(true)
-    end
-
-    it 'updates pii_from_doc in flow_session (even if nil)' do
-      flow_session[:pii_from_doc] = nil
-      expect do
-        put :update, params: params
-      end.to change { flow_session[:pii_from_doc] }.to eql(
-        pii_from_doc.merge(
-          {
-            'address1' => '1234 Main St',
-            'address2' => 'Apt B',
-            'city' => 'Beverly Hills',
-            'state' => 'CA',
-            'zipcode' => '90210',
-          },
-        ),
-      )
+      end.to change { subject.idv_session.address_edited }.from(nil).to eql(true)
     end
 
-    it 'updates pii_from_doc in idv_session (even if nil)' do
-      subject.idv_session.pii_from_doc = nil
+    it 'updates pii_from_doc in idv_session' do
       expect do
         put :update, params: params
-      end.to change { idv_session.pii_from_doc }.to eql(
+      end.to change { subject.idv_session.pii_from_doc }.to eql(
         pii_from_doc.merge(
           {
             'address1' => '1234 Main St',
diff --git a/spec/controllers/idv/document_capture_controller_spec.rb b/spec/controllers/idv/document_capture_controller_spec.rb
index 8e28c53f3ee..8de517414af 100644
--- a/spec/controllers/idv/document_capture_controller_spec.rb
+++ b/spec/controllers/idv/document_capture_controller_spec.rb
@@ -5,8 +5,6 @@
 
   let(:document_capture_session_uuid) { 'fd14e181-6fb1-4cdc-92e0-ef66dad0df4e' }
 
-  let(:flow_session) { {} }
-
   let(:user) { create(:user) }
 
   let(:ab_test_args) do
@@ -18,7 +16,6 @@
     stub_analytics
     subject.idv_session.flow_path = 'standard'
     subject.idv_session.document_capture_session_uuid = document_capture_session_uuid
-    subject.user_session['idv/doc_auth'] = flow_session
 
     allow(subject).to receive(:ab_test_analytics_buckets).and_return(ab_test_args)
   end
@@ -107,15 +104,6 @@
       end
     end
 
-    context 'with pii in flow session' do
-      it 'redirects to ssn step' do
-        flow_session[:pii_from_doc] = Idp::Constants::MOCK_IDV_APPLICANT
-        get :show
-
-        expect(response).to redirect_to(idv_ssn_url)
-      end
-    end
-
     context 'with pii in idv_session' do
       it 'redirects to ssn step' do
         subject.idv_session.pii_from_doc = Idp::Constants::MOCK_IDV_APPLICANT
diff --git a/spec/controllers/idv/in_person/verify_info_controller_spec.rb b/spec/controllers/idv/in_person/verify_info_controller_spec.rb
index eeaca608221..f5fc53dd0a1 100644
--- a/spec/controllers/idv/in_person/verify_info_controller_spec.rb
+++ b/spec/controllers/idv/in_person/verify_info_controller_spec.rb
@@ -5,9 +5,8 @@
 
   let(:pii_from_user) { Idp::Constants::MOCK_IDV_APPLICANT_SAME_ADDRESS_AS_ID.dup }
   let(:flow_session) do
-    { 'document_capture_session_uuid' => 'fd14e181-6fb1-4cdc-92e0-ef66dad0df4e',
-      :pii_from_user => pii_from_user,
-      :flow_path => 'standard' }
+    { pii_from_user: pii_from_user,
+      flow_path: 'standard' }
   end
 
   let(:user) { build(:user, :with_phone, with: { phone: '+1 (415) 555-0130' }) }
diff --git a/spec/controllers/idv/link_sent_controller_spec.rb b/spec/controllers/idv/link_sent_controller_spec.rb
index fb53f2d9c92..4745b5de372 100644
--- a/spec/controllers/idv/link_sent_controller_spec.rb
+++ b/spec/controllers/idv/link_sent_controller_spec.rb
@@ -3,8 +3,6 @@
 RSpec.describe Idv::LinkSentController do
   include IdvHelper
 
-  let(:flow_session) { {} }
-
   let(:user) { create(:user) }
 
   let(:ab_test_args) do
@@ -12,7 +10,6 @@
   end
 
   before do
-    allow(subject).to receive(:flow_session).and_return(flow_session)
     stub_sign_in(user)
     subject.idv_session.flow_path = 'hybrid'
     stub_analytics
@@ -97,15 +94,6 @@
       end
     end
 
-    context 'with pii in flow_session' do
-      it 'redirects to ssn step' do
-        flow_session[:pii_from_doc] = Idp::Constants::MOCK_IDV_APPLICANT
-        get :show
-
-        expect(response).to redirect_to(idv_ssn_url)
-      end
-    end
-
     context 'with pii in idv_session' do
       it 'redirects to ssn step' do
         subject.idv_session.pii_from_doc = Idp::Constants::MOCK_IDV_APPLICANT
diff --git a/spec/controllers/idv/sessions_controller_spec.rb b/spec/controllers/idv/sessions_controller_spec.rb
index c16c3fc9c24..b72c8e45de8 100644
--- a/spec/controllers/idv/sessions_controller_spec.rb
+++ b/spec/controllers/idv/sessions_controller_spec.rb
@@ -20,6 +20,7 @@
 
     let(:idv_session) { double }
     let(:flow_session) { { x: {} } }
+
     let(:pii) { { first_name: 'Jane' } }
 
     context 'when destroying the session' do
diff --git a/spec/controllers/idv/ssn_controller_spec.rb b/spec/controllers/idv/ssn_controller_spec.rb
index 6c62880c053..447c14127b8 100644
--- a/spec/controllers/idv/ssn_controller_spec.rb
+++ b/spec/controllers/idv/ssn_controller_spec.rb
@@ -3,10 +3,6 @@
 RSpec.describe Idv::SsnController do
   include IdvHelper
 
-  let(:flow_session) do
-    { pii_from_doc: Idp::Constants::MOCK_IDV_APPLICANT.dup }
-  end
-
   let(:ssn) { Idp::Constants::MOCK_IDV_APPLICANT_WITH_SSN[:ssn] }
 
   let(:user) { create(:user) }
@@ -17,7 +13,6 @@
 
   before do
     stub_sign_in(user)
-    subject.user_session['idv/doc_auth'] = flow_session
     subject.idv_session.flow_path = 'standard'
     subject.idv_session.pii_from_doc = Idp::Constants::MOCK_IDV_APPLICANT.dup
     stub_analytics
@@ -159,28 +154,6 @@
           from(nil).to(ssn)
       end
 
-      context 'with a Puerto Rico address and pii_from_doc in flow_session' do
-        before do
-          subject.idv_session.pii_from_doc = nil
-        end
-        it 'redirects to address controller after user enters their SSN' do
-          flow_session[:pii_from_doc][:state] = 'PR'
-
-          put :update, params: params
-
-          expect(response).to redirect_to(idv_address_url)
-        end
-
-        it 'redirects to the verify info controller if a user is updating their SSN' do
-          subject.idv_session.ssn = ssn
-          flow_session[:pii_from_doc][:state] = 'PR'
-
-          put :update, params: params
-
-          expect(response).to redirect_to(idv_verify_info_url)
-        end
-      end
-
       context 'with a Puerto Rico address and pii_from_doc in idv_session' do
         it 'redirects to address controller after user enters their SSN' do
           subject.idv_session.pii_from_doc[:state] = 'PR'
@@ -259,7 +232,6 @@
     context 'when pii_from_doc is not present' do
       before do
         subject.idv_session.flow_path = 'standard'
-        flow_session.delete(:pii_from_doc)
         subject.idv_session.pii_from_doc = nil
       end
 
diff --git a/spec/controllers/idv/verify_info_controller_spec.rb b/spec/controllers/idv/verify_info_controller_spec.rb
index 83db0a89456..632fc46fcd8 100644
--- a/spec/controllers/idv/verify_info_controller_spec.rb
+++ b/spec/controllers/idv/verify_info_controller_spec.rb
@@ -3,10 +3,6 @@
 RSpec.describe Idv::VerifyInfoController do
   include IdvHelper
 
-  let(:flow_session) do
-    { pii_from_doc: Idp::Constants::MOCK_IDV_APPLICANT.dup }
-  end
-
   let(:user) { create(:user) }
   let(:analytics_hash) do
     {
@@ -28,7 +24,6 @@
     subject.idv_session.flow_path = 'standard'
     subject.idv_session.pii_from_doc = Idp::Constants::MOCK_IDV_APPLICANT.dup
     subject.idv_session.ssn = Idp::Constants::MOCK_IDV_APPLICANT_WITH_SSN[:ssn]
-    subject.user_session['idv/doc_auth'] = flow_session
     allow(subject).to receive(:ab_test_analytics_buckets).and_return(ab_test_args)
   end
 
@@ -89,42 +84,19 @@
     context 'address line 2' do
       render_views
 
-      context 'pii_from_doc in flow_session' do
-        before do
-          subject.idv_session.pii_from_doc = nil
-        end
-
-        it 'With address2 in PII, shows address line 2 input' do
-          flow_session[:pii_from_doc][:address2] = 'APT 3E'
-          get :show
-
-          expect(response.body).to have_content(t('idv.form.address2'))
-        end
-
-        it 'No address2 in PII, still shows address line 2 input' do
-          flow_session[:pii_from_doc][:address2] = nil
-
-          get :show
+      it 'With address2 in PII, shows address line 2 input' do
+        subject.idv_session.pii_from_doc[:address2] = 'APT 3E'
+        get :show
 
-          expect(response.body).to have_content(t('idv.form.address2'))
-        end
+        expect(response.body).to have_content(t('idv.form.address2'))
       end
 
-      context 'pii_from_doc in idv_session' do
-        it 'With address2 in PII, shows address line 2 input' do
-          subject.idv_session.pii_from_doc[:address2] = 'APT 3E'
-          get :show
-
-          expect(response.body).to have_content(t('idv.form.address2'))
-        end
+      it 'No address2 in PII, still shows address line 2 input' do
+        subject.idv_session.pii_from_doc[:address2] = nil
 
-        it 'No address2 in PII, still shows address line 2 input' do
-          subject.idv_session.pii_from_doc[:address2] = nil
-
-          get :show
+        get :show
 
-          expect(response.body).to have_content(t('idv.form.address2'))
-        end
+        expect(response.body).to have_content(t('idv.form.address2'))
       end
     end
 
@@ -416,32 +388,15 @@
       expect(response).to redirect_to idv_verify_info_url
     end
 
-    context 'pii in flow_session' do
-      it 'modifies pii as expected' do
-        subject.idv_session.pii_from_doc = nil
-
-        app_id = 'hello-world'
-        sp = create(:service_provider, app_id: app_id)
-        sp_session = { issuer: sp.issuer }
-        allow(controller).to receive(:sp_session).and_return(sp_session)
-
-        put :update
-
-        expect(flow_session[:pii_from_doc][:uuid_prefix]).to eq app_id
-      end
-    end
-
-    context 'pii in idv_session' do
-      it 'modifies pii as expected' do
-        app_id = 'hello-world'
-        sp = create(:service_provider, app_id: app_id)
-        sp_session = { issuer: sp.issuer }
-        allow(controller).to receive(:sp_session).and_return(sp_session)
+    it 'modifies pii as expected' do
+      app_id = 'hello-world'
+      sp = create(:service_provider, app_id: app_id)
+      sp_session = { issuer: sp.issuer }
+      allow(controller).to receive(:sp_session).and_return(sp_session)
 
-        put :update
+      put :update
 
-        expect(subject.idv_session.pii_from_doc[:uuid_prefix]).to eq app_id
-      end
+      expect(subject.idv_session.pii_from_doc[:uuid_prefix]).to eq app_id
     end
 
     it 'updates DocAuthLog verify_submit_count' do
diff --git a/spec/forms/idv/ssn_format_form_spec.rb b/spec/forms/idv/ssn_format_form_spec.rb
index 26c0aa2e15e..10df8af324b 100644
--- a/spec/forms/idv/ssn_format_form_spec.rb
+++ b/spec/forms/idv/ssn_format_form_spec.rb
@@ -3,7 +3,6 @@
 RSpec.describe Idv::SsnFormatForm do
   let(:user) { create(:user) }
   let(:ssn) { '111-11-1111' }
-  let(:flow_session) { {} }
   let(:incoming_ssn) { nil }
 
   subject { Idv::SsnFormatForm.new(user, incoming_ssn) }
diff --git a/spec/views/idv/welcome/show.html.erb_spec.rb b/spec/views/idv/welcome/show.html.erb_spec.rb
index b9ab6b0aab2..e8824449022 100644
--- a/spec/views/idv/welcome/show.html.erb_spec.rb
+++ b/spec/views/idv/welcome/show.html.erb_spec.rb
@@ -1,7 +1,6 @@
 require 'rails_helper'
 
 RSpec.describe 'idv/welcome/show.html.erb' do
-  let(:flow_session) { {} }
   let(:user_fully_authenticated) { true }
   let(:sp_name) { nil }
   let(:user) { create(:user) }
@@ -10,7 +9,6 @@
     @decorated_sp_session = instance_double(ServiceProviderSession)
     allow(@decorated_sp_session).to receive(:sp_name).and_return(sp_name)
     allow(view).to receive(:decorated_sp_session).and_return(@decorated_sp_session)
-    allow(view).to receive(:flow_session).and_return(flow_session)
     allow(view).to receive(:user_fully_authenticated?).and_return(user_fully_authenticated)
     allow(view).to receive(:user_signing_up?).and_return(false)
     allow(view).to receive(:url_for).and_wrap_original do |method, *args, &block|