diff --git a/packages/url-loader/src/plugins/fill-background.ts b/packages/url-loader/src/plugins/fill-background.ts
index b5f7407..0234f38 100644
--- a/packages/url-loader/src/plugins/fill-background.ts
+++ b/packages/url-loader/src/plugins/fill-background.ts
@@ -21,6 +21,7 @@ export declare namespace FillBackgroundPlugin {
     crop?: CropMode;
     gravity?: Gravity;
     prompt?: ListablePrompts;
+    seed?: number;
   }
 }
 
@@ -64,16 +65,26 @@ export const FillBackgroundPlugin = /* #__PURE__ */ plugin({
 
       cldAsset.addTransformation(properties.join(","));
     } else if (typeof fillBackground === "object") {
-      const { crop = defaultCrop, gravity, prompt } = fillBackground;
+      const { crop = defaultCrop, gravity, prompt, seed } = fillBackground;
 
-      const properties = [`ar_${aspectRatio}`, `c_${crop}`];
+      const bGenFillProperties = [];
 
       if (typeof prompt === "string") {
-        properties.unshift(`b_gen_fill:${prompt}`);
-      } else {
-        properties.unshift(`b_gen_fill`);
+        bGenFillProperties.push(`prompt_${prompt}`);
       }
 
+      if (typeof seed === "number") {
+        bGenFillProperties.push(`seed_${seed}`);
+      }
+
+      const bGenFill = ( 
+        bGenFillProperties.length > 0 
+        ? `b_gen_fill:${bGenFillProperties.join(';')}`
+        : "b_gen_fill"
+      );
+
+      const properties = [ bGenFill, `ar_${aspectRatio}`, `c_${crop}`];
+
       if (typeof gravity === "string") {
         properties.push(`g_${gravity}`);
       }
diff --git a/packages/url-loader/tests/plugins/fill-background.spec.ts b/packages/url-loader/tests/plugins/fill-background.spec.ts
index cf5fc47..54028fa 100644
--- a/packages/url-loader/tests/plugins/fill-background.spec.ts
+++ b/packages/url-loader/tests/plugins/fill-background.spec.ts
@@ -41,13 +41,54 @@ describe("Plugins", () => {
           gravity: "east",
           prompt: "pink and purple flowers",
           crop: "mpad",
+          seed: 3
         },
       } as const;
 
       FillBackgroundPlugin.apply(cldImage, options);
 
       expect(cldImage.toURL()).toContain(
-        `b_gen_fill:${encodeURIComponent(options.fillBackground.prompt)},ar_${options.width}:${options.height},c_${options.fillBackground.crop},g_${options.fillBackground.gravity}/${TEST_PUBLIC_ID}`,
+        `b_gen_fill:prompt_${encodeURIComponent(options.fillBackground.prompt)};seed_3,ar_${options.width}:${options.height},c_${options.fillBackground.crop},g_${options.fillBackground.gravity}/${TEST_PUBLIC_ID}`,
+      );
+    });
+
+    it("should generate with just a seed but no prompt", () => {
+      const cldImage = cld.image(TEST_PUBLIC_ID);
+
+      const options = {
+        src: TEST_PUBLIC_ID,
+        width: 800,
+        height: 600,
+        fillBackground: {
+          crop: 'pad',
+          seed: 3
+        },
+      } as const;
+
+      FillBackgroundPlugin.apply(cldImage, options);
+
+      expect(cldImage.toURL()).toContain(
+        `b_gen_fill:seed_3,ar_${options.width}:${options.height},c_${options.fillBackground.crop}/${TEST_PUBLIC_ID}`,
+      );
+    });
+
+    it("should generate with just a prompt but no seed", () => {
+      const cldImage = cld.image(TEST_PUBLIC_ID);
+
+      const options = {
+        src: TEST_PUBLIC_ID,
+        width: 800,
+        height: 600,
+        fillBackground: {
+          crop: 'pad',
+          prompt: 'a herd of llamas'
+        },
+      } as const;
+
+      FillBackgroundPlugin.apply(cldImage, options);
+
+      expect(cldImage.toURL()).toContain(
+        `b_gen_fill:prompt_${encodeURIComponent(options.fillBackground.prompt)},ar_${options.width}:${options.height},c_${options.fillBackground.crop}/${TEST_PUBLIC_ID}`,
       );
     });
 
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 54d678c..3502432 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -3476,6 +3476,10 @@ packages:
     resolution: {integrity: sha512-R0XvVJ9WusLiqTCEiGCmICCMplcCkIwwR11mOSD9CR5u+IXYdiseeEuXCVAjS54zqwkLcPNnmU4OeJ6tUrWhDw==}
     engines: {node: '>=0.10.0'}
 
+  source-map-js@1.2.1:
+    resolution: {integrity: sha512-UXWMKhLOwVKb728IUtQPXxfYU+usdybtUrK/8uGE8CQMvrhOpwvzDBwj0QhSL7MQc7vIsISBG8VQ8+IDQxpfQA==}
+    engines: {node: '>=0.10.0'}
+
   source-map@0.6.1:
     resolution: {integrity: sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==}
     engines: {node: '>=0.10.0'}
@@ -5005,7 +5009,7 @@ snapshots:
   '@jridgewell/gen-mapping@0.3.5':
     dependencies:
       '@jridgewell/set-array': 1.2.1
-      '@jridgewell/sourcemap-codec': 1.4.15
+      '@jridgewell/sourcemap-codec': 1.5.0
       '@jridgewell/trace-mapping': 0.3.25
 
   '@jridgewell/resolve-uri@3.1.0': {}
@@ -5028,7 +5032,7 @@ snapshots:
   '@jridgewell/trace-mapping@0.3.25':
     dependencies:
       '@jridgewell/resolve-uri': 3.1.0
-      '@jridgewell/sourcemap-codec': 1.4.15
+      '@jridgewell/sourcemap-codec': 1.5.0
 
   '@next/eslint-plugin-next@14.2.4':
     dependencies:
@@ -6145,8 +6149,8 @@ snapshots:
       '@typescript-eslint/parser': 7.2.0(eslint@8.57.0)(typescript@5.5.2)
       eslint: 8.57.0
       eslint-import-resolver-node: 0.3.9
-      eslint-import-resolver-typescript: 3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0)
-      eslint-plugin-import: 2.29.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0))(eslint@8.57.0)
+      eslint-import-resolver-typescript: 3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0)
+      eslint-plugin-import: 2.29.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-typescript@3.6.1)(eslint@8.57.0)
       eslint-plugin-jsx-a11y: 6.9.0(eslint@8.57.0)
       eslint-plugin-react: 7.34.3(eslint@8.57.0)
       eslint-plugin-react-hooks: 4.6.2(eslint@8.57.0)
@@ -6170,13 +6174,13 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
-  eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0):
+  eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0):
     dependencies:
       debug: 4.3.6
       enhanced-resolve: 5.17.0
       eslint: 8.57.0
-      eslint-module-utils: 2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0))(eslint@8.57.0)
-      eslint-plugin-import: 2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0)
+      eslint-module-utils: 2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0))(eslint@8.57.0)
+      eslint-plugin-import: 2.29.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-typescript@3.6.1)(eslint@8.57.0)
       fast-glob: 3.3.2
       get-tsconfig: 4.7.5
       is-core-module: 2.13.1
@@ -6197,14 +6201,14 @@ snapshots:
     transitivePeerDependencies:
       - supports-color
 
-  eslint-module-utils@2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0))(eslint@8.57.0):
+  eslint-module-utils@2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0))(eslint@8.57.0):
     dependencies:
       debug: 3.2.7
     optionalDependencies:
       '@typescript-eslint/parser': 7.2.0(eslint@8.57.0)(typescript@5.5.2)
       eslint: 8.57.0
       eslint-import-resolver-node: 0.3.9
-      eslint-import-resolver-typescript: 3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0)
+      eslint-import-resolver-typescript: 3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0)
     transitivePeerDependencies:
       - supports-color
 
@@ -6235,7 +6239,7 @@ snapshots:
       - eslint-import-resolver-webpack
       - supports-color
 
-  eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0))(eslint@8.57.0):
+  eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-typescript@3.6.1)(eslint@8.57.0):
     dependencies:
       array-includes: 3.1.8
       array.prototype.findlastindex: 1.2.5
@@ -6245,7 +6249,7 @@ snapshots:
       doctrine: 2.1.0
       eslint: 8.57.0
       eslint-import-resolver-node: 0.3.9
-      eslint-module-utils: 2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1(@typescript-eslint/parser@7.18.0(eslint@8.57.0)(typescript@5.5.2))(eslint@8.57.0))(eslint@8.57.0))(eslint@8.57.0)
+      eslint-module-utils: 2.8.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-import-resolver-typescript@3.6.1(@typescript-eslint/parser@7.2.0(eslint@8.57.0)(typescript@5.5.2))(eslint-import-resolver-node@0.3.9)(eslint-plugin-import@2.29.1)(eslint@8.57.0))(eslint@8.57.0)
       hasown: 2.0.0
       is-core-module: 2.13.1
       is-glob: 4.0.3
@@ -7664,7 +7668,7 @@ snapshots:
     dependencies:
       chokidar: 3.5.3
       immutable: 4.3.4
-      source-map-js: 1.0.2
+      source-map-js: 1.2.1
     optional: true
 
   semantic-release-monorepo@7.0.5(semantic-release@20.1.0):
@@ -7789,6 +7793,9 @@ snapshots:
 
   source-map-js@1.0.2: {}
 
+  source-map-js@1.2.1:
+    optional: true
+
   source-map@0.6.1: {}
 
   source-map@0.8.0-beta.0: