diff --git a/packages/modules/b2c-core/src/api/vendor/campaigns/[id]/promotions/route.ts b/packages/modules/b2c-core/src/api/vendor/campaigns/[id]/promotions/route.ts
new file mode 100644
index 000000000..05fb56ce9
--- /dev/null
+++ b/packages/modules/b2c-core/src/api/vendor/campaigns/[id]/promotions/route.ts
@@ -0,0 +1,101 @@
+import {
+    AuthenticatedMedusaRequest,
+    MedusaResponse,
+  } from "@medusajs/framework/http"
+  
+  import { addOrRemoveCampaignPromotionsWorkflow } from "@medusajs/core-flows"
+  import { LinkMethodRequest } from "@medusajs/framework/types"
+  import { refetchCampaign } from "@medusajs/medusa/api/admin/campaigns/helpers"
+  
+/**
+ * @oas [post] /vendor/campaigns/{id}/promotions
+ * operationId: VendorPostCampaignsIdPromotions
+ * summary: Manage the Promotions of a Campaign
+ * description: Manage the promotions of a campaign, either by adding them or removing them from the campaign.
+ * x-authenticated: true
+ * parameters:
+ *   - name: id
+ *     in: path
+ *     description: The campaign's ID.
+ *     required: true
+ *     schema:
+ *       type: string
+ *   - name: fields
+ *     in: query
+ *     description: Comma-separated fields that should be included in the returned data. if a field is prefixed with `+` it will be added to the default fields, using `-` will remove it from the default
+ *       fields. without prefix it will replace the entire default fields.
+ *     required: false
+ *     schema:
+ *       type: string
+ *       title: fields
+ *       description: Comma-separated fields that should be included in the returned data. if a field is prefixed with `+` it will be added to the default fields, using `-` will remove it from the default
+ *         fields. without prefix it will replace the entire default fields.
+ *       externalDocs:
+ *         url: "#select-fields-and-relations"
+ * security:
+ *   - api_token: []
+ *   - cookie_auth: []
+ *   - jwt_token: []
+ * requestBody:
+ *   content:
+ *     application/json:
+ *       schema:
+ *         type: object
+ *         description: The promotions to add or remove from the campaign.
+ *         properties:
+ *           add:
+ *             type: array
+ *             description: The promotions to add to the campaign.
+ *             items:
+ *               type: string
+ *               title: add
+ *               description: A promotion's ID.
+ *           remove:
+ *             type: array
+ *             description: The promotions to remove from the campaign.
+ *             items:
+ *               type: string
+ *               title: remove
+ *               description: A promotion's ID.
+ * tags:
+ *   - Vendor Campaigns
+ * responses:
+ *   "200":
+ *     description: OK
+ *     content:
+ *       application/json:
+ *         schema:
+ *           $ref: "#/components/schemas/VendorCampaign"
+ *   "400":
+ *     $ref: "#/components/responses/400_error"
+ *   "401":
+ *     $ref: "#/components/responses/unauthorized"
+ *   "404":
+ *     $ref: "#/components/responses/not_found_error"
+ *   "409":
+ *     $ref: "#/components/responses/invalid_state_error"
+ *   "422":
+ *     $ref: "#/components/responses/invalid_request_error"
+ *   "500":
+ *     $ref: "#/components/responses/500_error"
+ * 
+*/
+
+  export const POST = async (
+    req: AuthenticatedMedusaRequest<LinkMethodRequest>,
+    res: MedusaResponse
+  ) => {
+    const { id } = req.params
+    const { add, remove } = req.validatedBody
+    await addOrRemoveCampaignPromotionsWorkflow(req.scope).run({
+      input: { id, add, remove },
+    })
+  
+    const campaign = await refetchCampaign(
+      req.params.id,
+      req.scope,
+      req.queryConfig.fields
+    )
+  
+    res.status(200).json({ campaign })
+  }
\ No newline at end of file
diff --git a/packages/modules/b2c-core/src/api/vendor/campaigns/middlewares.ts b/packages/modules/b2c-core/src/api/vendor/campaigns/middlewares.ts
index f9568dc8b..f09fa1611 100644
--- a/packages/modules/b2c-core/src/api/vendor/campaigns/middlewares.ts
+++ b/packages/modules/b2c-core/src/api/vendor/campaigns/middlewares.ts
@@ -15,6 +15,7 @@ import {
   VendorGetCampaignsParams,
   VendorUpdateCampaign
 } from './validators'
+import { createLinkBody } from '@medusajs/medusa/api/utils/validators'
 
 export const vendorCampaignsMiddlewares: MiddlewareRoute[] = [
   {
@@ -77,5 +78,16 @@ export const vendorCampaignsMiddlewares: MiddlewareRoute[] = [
         vendorCampaignQueryConfig.retrieve
       )
     ]
-  }
+  },
+  {
+    method: ["POST"],
+    matcher: "/vendor/campaigns/:id/promotions",
+    middlewares: [
+      validateAndTransformBody(createLinkBody()),
+      validateAndTransformQuery(
+        VendorGetCampaignsParams,
+        vendorCampaignQueryConfig.retrieve
+      ),
+    ],
+  },
 ]