diff --git a/README.md b/README.md
index 91902f2..96f4418 100644
--- a/README.md
+++ b/README.md
@@ -103,6 +103,7 @@ Options:
 | tags[].externalDocs.url                                   | `custom.documentation.tags.externalDocumentation.url`                                                                                                 |
 | tags[].externalDocs.description                           | `custom.documentation.tags.externalDocumentation.description`                                                                                         |
 | tags[].externalDocs.x-                                    | `custom.documentation.tags.externalDocumentation.x-` if extended specifications provided                                                              |
+| basePath                                                  | `custom.documentation.basePath`Specifies the base path to prepend to all Lambda HTTP function paths in the generated OpenAPI specification            |
 | paths                                                     | `custom.documentation.paths` OpenAPI paths that are not backed by Lambda functions                                                                    |
 | path[path]                                                | functions.functions.events.[http OR httpApi].path                                                                                                     |
 | path[path].servers[].description                          | functions.functions.servers.description                                                                                                               |
diff --git a/src/definitionGenerator.js b/src/definitionGenerator.js
index 4510900..980fc51 100644
--- a/src/definitionGenerator.js
+++ b/src/definitionGenerator.js
@@ -281,6 +281,18 @@ class DefinitionGenerator {
     const paths = this.serverless.service.custom.documentation.paths;
 
     if (paths) {
+      const basePath = this.getBasePath();
+
+      if (basePath) {
+        // check is paths's keys are not starting with `basePath` prefix and if set append it
+        for (const key of Object.keys(paths)) {
+          if (!key.startsWith(`/${basePath}`)) {
+            paths[`/${basePath}${key}`] = paths[key];
+            delete paths[key];
+          }
+        }
+      }
+
       const origPaths = this.openAPI.paths || {};
 
       Object.assign(this.openAPI, { paths: { ...origPaths, ...paths } });
@@ -288,19 +300,13 @@ class DefinitionGenerator {
   }
 
   /**
-   * @description Retrieves the basePath value if the domain manager plugin is used, allowing the server URL to be just the plain domain. The `basePath` will be prepended to each Lambda HTTP path.
+   * @description Retrieves the basePath value if set, allowing the server URL to be just the plain domain. The `basePath` will be prepended to each Lambda HTTP path. If `basePath` starts with a slash (/) returns the basePath without the leading slash.
    * @returns {string}
    */
   getBasePath() {
-    const plugins = this.serverless.service.plugins || [];
-
-    let basePath = "";
-
-    if (plugins.includes("serverless-domain-manager")) {
-      basePath = this.serverless.service.custom.basePath || "";
-    }
-
-    return basePath;
+    const basePath =
+      this.serverless.service.custom.documentation.basePath || "";
+    return basePath.replace(/^\//, "");
   }
 
   createServers(servers) {
diff --git a/test/helpers/serverless.js b/test/helpers/serverless.js
index fec3545..2417d82 100644
--- a/test/helpers/serverless.js
+++ b/test/helpers/serverless.js
@@ -1,19 +1,43 @@
-'use strict'
+"use strict";
 
 module.exports = {
-    processedInput: {
-        options: {
-            openApiVersion: '3.0.1'
-        }
+  processedInput: {
+    options: {
+      openApiVersion: "3.0.1",
     },
-    service: {
-        service: 'myAPI',
-        custom: {
-            documentation: {
-                title: 'My new API',
-                description: 'This API does things',
-                version: '0.0.1'
-            }
-        }
-    }
-}
+  },
+  service: {
+    service: "myAPI",
+    custom: {
+      documentation: {
+        title: "My new API",
+        description: "This API does things",
+        version: "0.0.1",
+        basePath: "v1",
+        paths: {
+          "/test/path": {
+            post: {
+              tags: ["Ttest Api"],
+              summary: "Test Api",
+              parameters: [
+                {
+                  in: "path",
+                  name: "id",
+                  required: true,
+                  schema: {
+                    type: "string",
+                  },
+                },
+              ],
+              responses: {
+                204: {
+                  description: "No content",
+                },
+              },
+            },
+          },
+        },
+      },
+    },
+  },
+};
diff --git a/test/unit/definitionGenerator.spec.js b/test/unit/definitionGenerator.spec.js
index 8f94c0a..27badd6 100644
--- a/test/unit/definitionGenerator.spec.js
+++ b/test/unit/definitionGenerator.spec.js
@@ -105,6 +105,44 @@ describe("DefinitionGenerator", () => {
       expect(expected.version).to.be.equal("3.0.0");
     });
 
+    it("should use the basePath when supplied", async function () {
+      const serverlessWithOpenAPIVersion = structuredClone(mockServerless);
+      const expected = new DefinitionGenerator(
+        serverlessWithOpenAPIVersion,
+        logger
+      );
+      const serverlessWithOpenAPIVersion2 = structuredClone(mockServerless);
+      delete serverlessWithOpenAPIVersion2.service.custom.documentation
+        .basePath;
+      const expectedWithoutBasePath = new DefinitionGenerator(
+        serverlessWithOpenAPIVersion2,
+        logger
+      );
+
+      expected.mergeExistingPaths();
+      expectedWithoutBasePath.mergeExistingPaths();
+
+      expect(expected.getBasePath()).to.be.equal(
+        serverlessWithOpenAPIVersion.service.custom.documentation.basePath
+      );
+      expect(
+        Object.keys(expected.openAPI.paths).every((key) =>
+          key.startsWith(`/${expected.getBasePath()}`)
+        )
+      ).to.be.equal(true);
+
+      expect(expectedWithoutBasePath.getBasePath()).to.be.equal("");
+      expect(
+        Object.keys(expectedWithoutBasePath.openAPI.paths).every((key, idx) =>
+          key.startsWith(
+            Object.keys(
+              serverlessWithOpenAPIVersion2.service.custom.documentation.paths
+            )[idx]
+          )
+        )
+      ).to.be.equal(true);
+    });
+
     it("should respect the version of openAPI when passed in", function () {
       const serverlessWithOpenAPIVersion = structuredClone(mockServerless);
       serverlessWithOpenAPIVersion.processedInput.options.openApiVersion =