diff --git a/app/components/chapter_picker_component.html.erb b/app/components/chapter_picker_component.html.erb
index 7d30afa31..eabbc20cf 100644
--- a/app/components/chapter_picker_component.html.erb
+++ b/app/components/chapter_picker_component.html.erb
@@ -2,6 +2,7 @@
                    list: datalist_id,
                    placeholder: @placeholder,
                    class: 'form-control',
+                   required: @required,
                    autocomplete: 'off' %>
 
 <%= tag.datalist id: datalist_id do %>
diff --git a/app/components/chapter_picker_component.rb b/app/components/chapter_picker_component.rb
index c74c52d79..ddb8eef71 100644
--- a/app/components/chapter_picker_component.rb
+++ b/app/components/chapter_picker_component.rb
@@ -1,12 +1,13 @@
 # frozen_string_literal: true
 
 class ChapterPickerComponent < ViewComponent::Base
-  def initialize(name:, chapters:, selected: nil, placeholder: 'Select a chapter')
+  def initialize(name:, chapters:, selected: nil, placeholder: 'Select a chapter', required: false)
     super()
     @name = name
     @chapters = chapters
     @selected = selected
     @placeholder = placeholder
+    @required = required
   end
 
   def datalist_id
diff --git a/app/models/workshop.rb b/app/models/workshop.rb
index 6c47b5ae8..02064f707 100644
--- a/app/models/workshop.rb
+++ b/app/models/workshop.rb
@@ -35,9 +35,9 @@ class Workshop < ApplicationRecord
   validates :student_spaces, numericality: { greater_than: 0 }, if: :virtual?
   validates :coach_spaces, numericality: { greater_than: 0 }, if: :virtual?
 
-  before_validation :set_date_and_time, :set_end_date_and_time, if: proc { |model| model.chapter_id.present? }
-  before_validation :set_opens_at
-  before_validation :set_closes_at
+  before_validation :set_date_and_time, :set_end_date_and_time,
+                    :set_opens_at, :set_closes_at,
+                    if: proc { |model| model.chapter_id.present? }
   validate :rsvp_date_time_fields_must_be_paired
   validate :rsvp_close_before_workshop_start
 
diff --git a/app/views/admin/workshops/_shared_form.html.haml b/app/views/admin/workshops/_shared_form.html.haml
index 02029483c..86729801d 100644
--- a/app/views/admin/workshops/_shared_form.html.haml
+++ b/app/views/admin/workshops/_shared_form.html.haml
@@ -3,13 +3,13 @@
     = f.hidden_field :chapter_id
   - else
     .col-12
-      = render(ChapterPickerComponent.new(name: 'workshop[chapter_id]', chapters: Chapter.available_to_user(current_user), placeholder: 'Select a chapter'))
+      = render(ChapterPickerComponent.new(name: 'workshop[chapter_id]', chapters: Chapter.available_to_user(current_user), placeholder: 'Select a chapter', required: true))
   .col-12
-    = f.input :local_date, label: 'Date', required: true, input_html: { value: @workshop.date_and_time.try(:strftime, '%Y-%m-%d'), type: :date }
+    = f.input :local_date, label: 'Date', required: true, input_html: { value: @workshop.local_date.presence || @workshop.date_and_time.try(:strftime, '%Y-%m-%d'), type: :date }
   .col-12.col-md-6
-    = f.input :local_time, label: 'Begins at', required: true, input_html: { value: @workshop.time.try(:strftime, '%H:%M'), type: :time }
+    = f.input :local_time, label: 'Begins at', required: true, input_html: { value: @workshop.local_time.presence || @workshop.time.try(:strftime, '%H:%M'), type: :time }
   .col-12.col-md-6
-    = f.input :local_end_time, label: 'Ends at', required: true, input_html: { value: @workshop.ends_at.try(:strftime, '%H:%M'), type: :time }
+    = f.input :local_end_time, label: 'Ends at', required: true, input_html: { value: @workshop.local_end_time.presence || @workshop.ends_at.try(:strftime, '%H:%M'), type: :time }
   .col-12#host
     = f.input :host, as: :select, collection: Sponsor.all, include_blank: true, selected: (@workshop.host.id rescue '')
   .col-12
@@ -27,11 +27,11 @@
         %p.small.text-muted= t('admin.workshop.form.rsvp_details')
         .row
           .col-12.col-md-6
-            = f.input :rsvp_open_local_date, label: 'Open date', input_html: { value: @workshop.rsvp_opens_at.try(:strftime, '%Y-%m-%d'), type: :date }
+            = f.input :rsvp_open_local_date, label: 'Open date', input_html: { value: @workshop.rsvp_open_local_date.presence || @workshop.rsvp_opens_at.try(:strftime, '%Y-%m-%d'), type: :date }
           .col-12.col-md-6
-            = f.input :rsvp_open_local_time, label: 'Open time', input_html: { value: @workshop.rsvp_opens_at.try(:time).try(:strftime, '%H:%M'), type: :time }
+            = f.input :rsvp_open_local_time, label: 'Open time', input_html: { value: @workshop.rsvp_open_local_time.presence || @workshop.rsvp_opens_at.try(:time).try(:strftime, '%H:%M'), type: :time }
         .row
           .col-12.col-md-6
-            = f.input :rsvp_close_local_date, label: 'Close date', input_html: { value: @workshop.rsvp_closes_at.try(:strftime, '%Y-%m-%d'), type: :date }
+            = f.input :rsvp_close_local_date, label: 'Close date', input_html: { value: @workshop.rsvp_close_local_date.presence || @workshop.rsvp_closes_at.try(:strftime, '%Y-%m-%d'), type: :date }
           .col-12.col-md-6
-            = f.input :rsvp_close_local_time, label: 'Close time', input_html: { value: @workshop.rsvp_closes_at.try(:time).try(:strftime, '%H:%M'), type: :time }
+            = f.input :rsvp_close_local_time, label: 'Close time', input_html: { value: @workshop.rsvp_close_local_time.presence || @workshop.rsvp_closes_at.try(:time).try(:strftime, '%H:%M'), type: :time }
diff --git a/spec/controllers/admin/workshops_controller_spec.rb b/spec/controllers/admin/workshops_controller_spec.rb
index 1f2db20ac..990a27426 100644
--- a/spec/controllers/admin/workshops_controller_spec.rb
+++ b/spec/controllers/admin/workshops_controller_spec.rb
@@ -162,6 +162,8 @@ def assigns(symbol)
   end
 
   describe 'POST #create' do
+    let(:sponsor) { Fabricate(:sponsor) }
+
     it 'permits rsvp_close_local_date and rsvp_close_local_time' do
       expect do
         post :create, params: { workshop: { rsvp_close_local_date: '01/12/2020', rsvp_close_local_time: '15:00', host: '' } }
@@ -187,6 +189,36 @@ def assigns(symbol)
       expect(PublicActivity::Activity.exists?(owner: admin, key: 'workshop.created',
                                               trackable: created)).to be(true)
     end
+
+    context 'when no chapter is selected' do
+      render_views
+
+      def create_workshop
+        post :create, params: {
+          workshop: {
+            chapter_id: '', local_date: '2026-09-21', local_time: '18:00',
+            local_end_time: '22:00', host: sponsor.id.to_s,
+            sponsor_ids: ['', sponsor.id.to_s], description: '',
+            rsvp_open_local_date: '', rsvp_open_local_time: '',
+            rsvp_close_local_date: '2026-09-21', rsvp_close_local_time: '14:30',
+            virtual: '0', coach_spaces: '0', student_spaces: '0', invitable: '1'
+          }
+        }
+      end
+
+      it 'renders the form with a validation warning instead of raising' do
+        expect { create_workshop }.not_to raise_error
+        expect(response).to have_http_status(:ok)
+        expect(flash[:warning]).to include("Chapter can't be blank")
+      end
+
+      it 'keeps the submitted RSVP close values in the form' do
+        create_workshop
+
+        expect(response.body).to include('value="2026-09-21"')
+        expect(response.body).to include('value="14:30"')
+      end
+    end
   end
 
   describe 'DELETE #destroy' do