diff --git a/app/models/spree/adjustment.rb b/app/models/spree/adjustment.rb
index cb965b8aef..93f4bbafe2 100644
--- a/app/models/spree/adjustment.rb
+++ b/app/models/spree/adjustment.rb
@@ -39,6 +39,8 @@ module Spree
     belongs_to :adjustable, polymorphic: true
     belongs_to :source, polymorphic: true
     belongs_to :originator, polymorphic: true
+    belongs_to :order, class_name: "Spree::Order"
+
     belongs_to :tax_rate, -> { where spree_adjustments: { originator_type: 'Spree::TaxRate' } },
                foreign_key: 'originator_id'
 
diff --git a/app/models/spree/tax_rate.rb b/app/models/spree/tax_rate.rb
index 84a0a7b0dd..0721e127fd 100644
--- a/app/models/spree/tax_rate.rb
+++ b/app/models/spree/tax_rate.rb
@@ -71,6 +71,7 @@ module Spree
             amount: amount,
             source: order,
             originator: self,
+            order: order,
             state: "closed",
             label: label
           )
diff --git a/db/migrate/20201219120055_add_order_to_adjustments.rb b/db/migrate/20201219120055_add_order_to_adjustments.rb
new file mode 100644
index 0000000000..718701d16c
--- /dev/null
+++ b/db/migrate/20201219120055_add_order_to_adjustments.rb
@@ -0,0 +1,18 @@
+class AddOrderToAdjustments < ActiveRecord::Migration
+  def up
+    add_column :spree_adjustments, :order_id, :integer
+
+    # Ensure migration can use the new column
+    Spree::Adjustment.reset_column_information
+
+    # Migrate adjustments on orders
+    Spree::Adjustment.where(order_id: nil, adjustable_type: "Spree::Order").find_each do |adjustment|
+      adjustment.update_column(:order_id, adjustment.adjustable_id)
+    end
+
+    # Migrate adjustments on line_items
+    Spree::Adjustment.where(order_id: nil, adjustable_type: "Spree::LineItem").includes(:adjustable).find_each do |adjustment|
+      adjustment.update_column(:order_id, adjustment.adjustable.order_id)
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index e71191e567..3d4de3b876 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -11,7 +11,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema.define(version: 20201113163227) do
+ActiveRecord::Schema.define(version: 20201219120055) do
 
   # These are extensions that must be enabled in order to support this database
   enable_extension "plpgsql"
@@ -393,6 +393,7 @@ ActiveRecord::Schema.define(version: 20201113163227) do
     t.string   "adjustable_type", limit: 255
     t.decimal  "included_tax",                precision: 10, scale: 2, default: 0.0,  null: false
     t.string   "state",           limit: 255
+    t.integer  "order_id"
   end
 
   add_index "spree_adjustments", ["adjustable_id"], name: "index_adjustments_on_order_id", using: :btree
diff --git a/lib/spree/core/calculated_adjustments.rb b/lib/spree/core/calculated_adjustments.rb
index c502c00099..6388369209 100644
--- a/lib/spree/core/calculated_adjustments.rb
+++ b/lib/spree/core/calculated_adjustments.rb
@@ -40,6 +40,7 @@ module Spree
               amount: amount,
               source: old_calculable,
               originator: self,
+              order: order_object_for(target),
               label: label,
               mandatory: mandatory,
               state: state
@@ -74,6 +75,17 @@ module Spree
             Rails.application.config.spree.calculators
           end
           private_class_method :spree_calculators
+
+          private
+
+          def order_object_for(target)
+            # Temporary method for adjustments transition.
+            if target.is_a? Spree::Order
+              target
+            elsif target.respond_to?(:order)
+              target.order
+            end
+          end
         end
       end
     end
diff --git a/spec/lib/spree/core/calculated_adjustments_spec.rb b/spec/lib/spree/core/calculated_adjustments_spec.rb
index b9210c4f29..484654e2eb 100644
--- a/spec/lib/spree/core/calculated_adjustments_spec.rb
+++ b/spec/lib/spree/core/calculated_adjustments_spec.rb
@@ -28,6 +28,11 @@ describe Spree::Core::CalculatedAdjustments do
       tax_rate.create_adjustment("foo", target, order)
     end
 
+    it "should be associated with the order" do
+      tax_rate.create_adjustment("foo", target, order)
+      expect(target.adjustments.first.order_id).to eq order.id
+    end
+
     it "should have the correct originator and an amount derived from the calculator and supplied calculable" do
       adjustment = tax_rate.create_adjustment("foo", target, order)
       expect(adjustment).not_to be_nil