diff --git a/.rubocop_todo.yml b/.rubocop_todo.yml
index 6eb6712cce..de959163db 100644
--- a/.rubocop_todo.yml
+++ b/.rubocop_todo.yml
@@ -681,6 +681,7 @@ Metrics/ClassLength:
     - 'app/models/spree/payment.rb'
     - 'app/models/spree/product.rb'
     - 'app/models/spree/shipment.rb'
+    - 'app/models/spree/shipping_method.rb'
     - 'app/models/spree/user.rb'
     - 'app/models/spree/variant.rb'
     - 'app/models/spree/zone.rb'
diff --git a/app/models/adjustment_metadata.rb b/app/models/adjustment_metadata.rb
index eb99ad1de7..4753592a46 100644
--- a/app/models/adjustment_metadata.rb
+++ b/app/models/adjustment_metadata.rb
@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 class AdjustmentMetadata < ApplicationRecord
+  self.belongs_to_required_by_default = true
+
   belongs_to :adjustment, class_name: 'Spree::Adjustment'
   belongs_to :enterprise
 end
diff --git a/app/models/column_preference.rb b/app/models/column_preference.rb
index 3a08aa3a85..adcc6999bd 100644
--- a/app/models/column_preference.rb
+++ b/app/models/column_preference.rb
@@ -5,6 +5,8 @@ require 'open_food_network/column_preference_defaults'
 class ColumnPreference < ApplicationRecord
   extend OpenFoodNetwork::ColumnPreferenceDefaults
 
+  self.belongs_to_required_by_default = true
+
   # Non-persisted attributes that only have one
   # setting (ie. the default) for a given column
   attr_accessor :name
diff --git a/app/models/coordinator_fee.rb b/app/models/coordinator_fee.rb
index b308c611b1..4a69085e03 100644
--- a/app/models/coordinator_fee.rb
+++ b/app/models/coordinator_fee.rb
@@ -1,6 +1,8 @@
 # frozen_string_literal: true
 
 class CoordinatorFee < ApplicationRecord
+  self.belongs_to_required_by_default = true
+
   belongs_to :order_cycle
   belongs_to :enterprise_fee
 end
diff --git a/app/models/customer.rb b/app/models/customer.rb
index 6e5468fed1..c0dbf6d8a7 100644
--- a/app/models/customer.rb
+++ b/app/models/customer.rb
@@ -10,20 +10,22 @@
 class Customer < ApplicationRecord
   include SetUnusedAddressFields
 
+  self.belongs_to_required_by_default = true
+
   acts_as_taggable
 
   searchable_attributes :first_name, :last_name, :email, :code
 
-  belongs_to :enterprise, optional: false
-  belongs_to :user, class_name: "Spree::User"
+  belongs_to :enterprise
+  belongs_to :user, class_name: "Spree::User", optional: true
   has_many :orders, class_name: "Spree::Order"
   before_destroy :update_orders_and_delete_canceled_subscriptions
 
-  belongs_to :bill_address, class_name: "Spree::Address"
+  belongs_to :bill_address, class_name: "Spree::Address", optional: true
   alias_attribute :billing_address, :bill_address
   accepts_nested_attributes_for :bill_address
 
-  belongs_to :ship_address, class_name: "Spree::Address"
+  belongs_to :ship_address, class_name: "Spree::Address", optional: true
   alias_attribute :shipping_address, :ship_address
   accepts_nested_attributes_for :ship_address
 
diff --git a/app/models/distributor_payment_method.rb b/app/models/distributor_payment_method.rb
index d4cf9f6d1d..57287f4422 100644
--- a/app/models/distributor_payment_method.rb
+++ b/app/models/distributor_payment_method.rb
@@ -2,6 +2,8 @@
 
 class DistributorPaymentMethod < ApplicationRecord
   self.table_name = "distributors_payment_methods"
+  self.belongs_to_required_by_default = true
+
   belongs_to :payment_method, class_name: "Spree::PaymentMethod", touch: true
   belongs_to :distributor, class_name: "Enterprise", touch: true
 end
diff --git a/app/models/distributor_shipping_method.rb b/app/models/distributor_shipping_method.rb
index ebce5682bc..bb09eaec5f 100644
--- a/app/models/distributor_shipping_method.rb
+++ b/app/models/distributor_shipping_method.rb
@@ -2,6 +2,8 @@
 
 class DistributorShippingMethod < ApplicationRecord
   self.table_name = "distributors_shipping_methods"
+  self.belongs_to_required_by_default = true
+
   belongs_to :shipping_method, class_name: "Spree::ShippingMethod", touch: true
   belongs_to :distributor, class_name: "Enterprise", touch: true
 end
diff --git a/app/models/enterprise.rb b/app/models/enterprise.rb
index e7b81947ae..9b74a711a5 100644
--- a/app/models/enterprise.rb
+++ b/app/models/enterprise.rb
@@ -61,8 +61,10 @@ class Enterprise < ApplicationRecord
   has_many :users, through: :enterprise_roles
   belongs_to :owner, class_name: 'Spree::User',
                      inverse_of: :owned_enterprises
-  has_many :distributor_payment_methods, foreign_key: :distributor_id
-  has_many :distributor_shipping_methods, foreign_key: :distributor_id
+  has_many :distributor_payment_methods,
+    inverse_of: :distributor, foreign_key: :distributor_id
+  has_many :distributor_shipping_methods,
+    inverse_of: :distributor, foreign_key: :distributor_id
   has_many :payment_methods, through: :distributor_payment_methods
   has_many :shipping_methods, through: :distributor_shipping_methods
   has_many :customers
diff --git a/app/models/spree/shipping_method.rb b/app/models/spree/shipping_method.rb
index 89941d6ccd..0e023413ab 100644
--- a/app/models/spree/shipping_method.rb
+++ b/app/models/spree/shipping_method.rb
@@ -8,6 +8,8 @@ module Spree
       back_end: "back_end"
     }.freeze
 
+    self.belongs_to_required_by_default = true
+
     acts_as_paranoid
     acts_as_taggable
 
@@ -25,7 +27,7 @@ module Spree
     has_and_belongs_to_many :zones, join_table: 'spree_shipping_methods_zones',
                                     class_name: 'Spree::Zone'
 
-    belongs_to :tax_category, class_name: 'Spree::TaxCategory'
+    belongs_to :tax_category, class_name: 'Spree::TaxCategory', optional: true
 
     validates :name, presence: true
     validate :distributor_validation
diff --git a/db/migrate/20230503060530_require_adjustment_and_enterprise_on_adjustment_metadata.rb b/db/migrate/20230503060530_require_adjustment_and_enterprise_on_adjustment_metadata.rb
new file mode 100644
index 0000000000..e13fdf4b72
--- /dev/null
+++ b/db/migrate/20230503060530_require_adjustment_and_enterprise_on_adjustment_metadata.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class RequireAdjustmentAndEnterpriseOnAdjustmentMetadata < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null :adjustment_metadata, :adjustment_id, false
+    change_column_null :adjustment_metadata, :enterprise_id, false
+  end
+end
diff --git a/db/migrate/20230516052547_require_order_cycle_and_enterprise_fee_on_coordinator_fees.rb b/db/migrate/20230516052547_require_order_cycle_and_enterprise_fee_on_coordinator_fees.rb
new file mode 100644
index 0000000000..6cef109289
--- /dev/null
+++ b/db/migrate/20230516052547_require_order_cycle_and_enterprise_fee_on_coordinator_fees.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class RequireOrderCycleAndEnterpriseFeeOnCoordinatorFees < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null :coordinator_fees, :order_cycle_id, false
+    change_column_null :coordinator_fees, :enterprise_fee_id, false
+  end
+end
diff --git a/db/migrate/20230516054204_require_payment_method_and_distributor_on_distributor_payment_methods.rb b/db/migrate/20230516054204_require_payment_method_and_distributor_on_distributor_payment_methods.rb
new file mode 100644
index 0000000000..38ead36d6f
--- /dev/null
+++ b/db/migrate/20230516054204_require_payment_method_and_distributor_on_distributor_payment_methods.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class RequirePaymentMethodAndDistributorOnDistributorPaymentMethods < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null :distributors_payment_methods, :payment_method_id, false
+    change_column_null :distributors_payment_methods, :distributor_id, false
+  end
+end
diff --git a/db/migrate/20230516054745_require_shipping_method_and_distributor_on_distributor_shipping_methods.rb b/db/migrate/20230516054745_require_shipping_method_and_distributor_on_distributor_shipping_methods.rb
new file mode 100644
index 0000000000..0a55501242
--- /dev/null
+++ b/db/migrate/20230516054745_require_shipping_method_and_distributor_on_distributor_shipping_methods.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+class RequireShippingMethodAndDistributorOnDistributorShippingMethods < ActiveRecord::Migration[7.0]
+  def change
+    change_column_null :distributors_shipping_methods, :shipping_method_id, false
+    change_column_null :distributors_shipping_methods, :distributor_id, false
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index 1241b84131..71537c92ce 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -44,8 +44,8 @@ ActiveRecord::Schema[7.0].define(version: 2023_05_22_120633) do
   end
 
   create_table "adjustment_metadata", id: :serial, force: :cascade do |t|
-    t.integer "adjustment_id"
-    t.integer "enterprise_id"
+    t.integer "adjustment_id", null: false
+    t.integer "enterprise_id", null: false
     t.string "fee_name", limit: 255
     t.string "fee_type", limit: 255
     t.string "enterprise_role", limit: 255
@@ -64,8 +64,8 @@ ActiveRecord::Schema[7.0].define(version: 2023_05_22_120633) do
   end
 
   create_table "coordinator_fees", id: :serial, force: :cascade do |t|
-    t.integer "order_cycle_id"
-    t.integer "enterprise_fee_id"
+    t.integer "order_cycle_id", null: false
+    t.integer "enterprise_fee_id", null: false
     t.index ["enterprise_fee_id"], name: "index_coordinator_fees_on_enterprise_fee_id"
     t.index ["order_cycle_id"], name: "index_coordinator_fees_on_order_cycle_id"
   end
@@ -116,8 +116,8 @@ ActiveRecord::Schema[7.0].define(version: 2023_05_22_120633) do
   end
 
   create_table "distributors_payment_methods", force: :cascade do |t|
-    t.integer "distributor_id"
-    t.integer "payment_method_id"
+    t.integer "distributor_id", null: false
+    t.integer "payment_method_id", null: false
     t.datetime "created_at", precision: nil
     t.datetime "updated_at", precision: nil
     t.index ["distributor_id"], name: "index_distributors_payment_methods_on_distributor_id"
@@ -125,8 +125,8 @@ ActiveRecord::Schema[7.0].define(version: 2023_05_22_120633) do
   end
 
   create_table "distributors_shipping_methods", id: :serial, force: :cascade do |t|
-    t.integer "distributor_id"
-    t.integer "shipping_method_id"
+    t.integer "distributor_id", null: false
+    t.integer "shipping_method_id", null: false
     t.datetime "created_at", precision: nil, null: false
     t.datetime "updated_at", precision: nil, null: false
     t.index ["distributor_id"], name: "index_distributors_shipping_methods_on_distributor_id"
diff --git a/spec/models/adjustment_metadata_spec.rb b/spec/models/adjustment_metadata_spec.rb
index 13657826b4..66ae5bc6f0 100644
--- a/spec/models/adjustment_metadata_spec.rb
+++ b/spec/models/adjustment_metadata_spec.rb
@@ -3,6 +3,9 @@
 require 'spec_helper'
 
 describe AdjustmentMetadata do
+  it { is_expected.to belong_to(:adjustment).required }
+  it { is_expected.to belong_to(:enterprise).required }
+
   it "is valid when built from factory" do
     adjustment_metadata = build(:adjustment_metadata)
     expect(adjustment_metadata).to be_valid
diff --git a/spec/models/column_preference_spec.rb b/spec/models/column_preference_spec.rb
index 108c76b4ac..cfb51edb3d 100644
--- a/spec/models/column_preference_spec.rb
+++ b/spec/models/column_preference_spec.rb
@@ -3,19 +3,27 @@
 require 'spec_helper'
 
 describe ColumnPreference, type: :model do
+  subject {
+    ColumnPreference.new(
+      user: user, action_name: :customers_index, column_name: :email
+    )
+  }
+  let(:user) { build(:user) }
+
+  it { is_expected.to belong_to(:user).required }
+
   describe "finding stored preferences for a user and action" do
     before do
       allow(ColumnPreference).to receive(:known_actions) { ['some_action'] }
       allow(ColumnPreference).to receive(:valid_columns_for) { ['col1', 'col2', 'col3'] }
     end
 
-    let(:user) { create(:user) }
     let!(:col1_pref) {
-      ColumnPreference.create(user_id: user.id, action_name: 'some_action', column_name: 'col1',
+      ColumnPreference.create(user: user, action_name: 'some_action', column_name: 'col1',
                               visible: true)
     }
     let!(:col2_pref) {
-      ColumnPreference.create(user_id: user.id, action_name: 'some_action', column_name: 'col2',
+      ColumnPreference.create(user: user, action_name: 'some_action', column_name: 'col2',
                               visible: false)
     }
     let(:defaults) {
diff --git a/spec/models/coordinator_fee_spec.rb b/spec/models/coordinator_fee_spec.rb
new file mode 100644
index 0000000000..5e3a8765b8
--- /dev/null
+++ b/spec/models/coordinator_fee_spec.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe CoordinatorFee do
+  it { is_expected.to belong_to(:order_cycle).required }
+  it { is_expected.to belong_to(:enterprise_fee).required }
+end
diff --git a/spec/models/customer_spec.rb b/spec/models/customer_spec.rb
index 1b4f93cf02..8cf26c69d0 100644
--- a/spec/models/customer_spec.rb
+++ b/spec/models/customer_spec.rb
@@ -3,6 +3,11 @@
 require 'spec_helper'
 
 describe Customer, type: :model do
+  it { is_expected.to belong_to(:enterprise).required }
+  it { is_expected.to belong_to(:user).optional }
+  it { is_expected.to belong_to(:bill_address).optional }
+  it { is_expected.to belong_to(:ship_address).optional }
+
   describe 'an existing customer' do
     let(:customer) { create(:customer) }