diff --git a/app/models/alt_style.rb b/app/models/alt_style.rb
index 5eccdee1..53d958b6 100644
--- a/app/models/alt_style.rb
+++ b/app/models/alt_style.rb
@@ -11,6 +11,7 @@ class AltStyle < ApplicationRecord
   validates :body_id, presence: true
 
   before_create :infer_series_name
+  before_create :infer_thumbnail_url
 
   scope :matching_name, ->(series_name, color_name, species_name) {
     color = Color.find_by_name!(color_name)
@@ -41,22 +42,6 @@ class AltStyle < ApplicationRecord
     "#{series_name} #{color.human_name}"
   end
 
-  THUMBNAIL_URL_TEMPLATE = Addressable::Template.new(
-    "https://images.neopets.com/items/{series}_{color}_{species}.gif"
-  )
-  DEFAULT_THUMBNAIL_URL = "https://images.neopets.com/items/mall_bg_circle.gif"
-  def thumbnail_url
-    return DEFAULT_THUMBNAIL_URL unless has_real_series_name?
-
-    # HACK: We're assuming this is the format long-term! But if it changes, we
-    # may need to add it as a database field instead.
-    THUMBNAIL_URL_TEMPLATE.expand(
-      series: series_name.gsub(/\s+/, '').downcase,
-      color: color.name.gsub(/\s+/, '').downcase,
-      species: species.name.gsub(/\s+/, '').downcase,
-    ).to_s
-  end
-
   def preview_image_url
     swf_asset = swf_assets.first
     return nil if swf_asset.nil?
@@ -91,6 +76,26 @@ class AltStyle < ApplicationRecord
     end
   end
 
+  # At time of writing, most batches of Alt Styles thumbnails used a simple
+  # pattern for the item thumbnail URL, but that's not always the case anymore.
+  # For now, let's keep using this format as the default value when creating a
+  # new Alt Style, but the database field can be manually overridden as needed!
+  THUMBNAIL_URL_TEMPLATE = Addressable::Template.new(
+    "https://images.neopets.com/items/{series}_{color}_{species}.gif"
+  )
+  DEFAULT_THUMBNAIL_URL = "https://images.neopets.com/items/mall_bg_circle.gif"
+  def infer_thumbnail_url
+    if has_real_series_name?
+      self.thumbnail_url = THUMBNAIL_URL_TEMPLATE.expand(
+        series: series_name.gsub(/\s+/, '').downcase,
+        color: color.name.gsub(/\s+/, '').downcase,
+        species: species.name.gsub(/\s+/, '').downcase,
+      ).to_s
+    else
+      self.thumbnail_url = DEFAULT_THUMBNAIL_URL
+    end
+  end
+
   # For convenience in the console!
   def self.find_by_name(color_name, species_name)
     color = Color.find_by_name(color_name)
diff --git a/db/migrate/20240616001002_add_thumbnail_url_to_alt_styles.rb b/db/migrate/20240616001002_add_thumbnail_url_to_alt_styles.rb
new file mode 100644
index 00000000..ea8ffc80
--- /dev/null
+++ b/db/migrate/20240616001002_add_thumbnail_url_to_alt_styles.rb
@@ -0,0 +1,14 @@
+class AddThumbnailUrlToAltStyles < ActiveRecord::Migration[7.1]
+  def change
+    add_column :alt_styles, :thumbnail_url, :string, null: false
+
+    reversible do |direction|
+      direction.up do
+        AltStyle.find_each do |alt_style|
+          alt_style.infer_thumbnail_url
+          alt_style.save!
+        end
+      end
+    end
+  end
+end
diff --git a/db/schema.rb b/db/schema.rb
index f071ff9a..2fd7b016 100644
--- a/db/schema.rb
+++ b/db/schema.rb
@@ -10,7 +10,7 @@
 #
 # It's strongly recommended that you check this file into your version control system.
 
-ActiveRecord::Schema[7.1].define(version: 2024_06_08_022149) do
+ActiveRecord::Schema[7.1].define(version: 2024_06_16_001002) do
   create_table "alt_styles", charset: "utf8mb4", collation: "utf8mb4_unicode_520_ci", force: :cascade do |t|
     t.integer "species_id", null: false
     t.integer "color_id", null: false
@@ -18,6 +18,7 @@ ActiveRecord::Schema[7.1].define(version: 2024_06_08_022149) do
     t.datetime "created_at", precision: nil, null: false
     t.datetime "updated_at", precision: nil, null: false
     t.string "series_name"
+    t.string "thumbnail_url", null: false
     t.index ["color_id"], name: "index_alt_styles_on_color_id"
     t.index ["species_id"], name: "index_alt_styles_on_species_id"
   end