diff --git a/lib/Client/index.ts b/lib/Client/index.ts
index 843c296..2b0fa08 100644
--- a/lib/Client/index.ts
+++ b/lib/Client/index.ts
@@ -1,12 +1,12 @@
 import { State } from '@voiceflow/runtime';
-import axios, { AxiosInstance } from 'axios';
+import axios, { AxiosInstance, AxiosRequestConfig } from 'axios';
 import _cloneDeep from 'lodash/cloneDeep';
 
 import { RequestContext, ResponseContext } from '@/lib/types';
 
 import { adaptResponseContext, extractAudioStep } from './adapters';
 
-export type ClientConfig<S> = { variables?: Partial<S>; endpoint: string; versionID: string };
+export type ClientConfig<S> = { variables?: Partial<S>; endpoint: string; versionID: string; axiosConfig?: AxiosRequestConfig };
 
 export class Client<S extends Record<string, any> = Record<string, any>> {
   private axios: AxiosInstance;
@@ -17,8 +17,8 @@ export class Client<S extends Record<string, any> = Record<string, any>> {
 
   private initVariables: Partial<S> | undefined;
 
-  constructor({ variables, endpoint, versionID }: ClientConfig<S>) {
-    this.axios = axios.create({ baseURL: endpoint });
+  constructor({ variables, endpoint, versionID, axiosConfig }: ClientConfig<S>) {
+    this.axios = axios.create({ ...axiosConfig, baseURL: endpoint });
 
     this.initVariables = variables;
     this.versionID = versionID;
diff --git a/lib/RuntimeClientFactory/index.ts b/lib/RuntimeClientFactory/index.ts
index afba684..084cbca 100644
--- a/lib/RuntimeClientFactory/index.ts
+++ b/lib/RuntimeClientFactory/index.ts
@@ -1,4 +1,5 @@
 import { State } from '@voiceflow/runtime';
+import { AxiosRequestConfig } from 'axios';
 
 import Client from '@/lib/Client';
 import RuntimeClient from '@/lib/RuntimeClient';
@@ -12,6 +13,7 @@ export type FactoryConfig<S extends State['variables']> = {
   endpoint?: string;
   dataConfig?: DataConfig;
   variables?: Partial<S>;
+  axiosConfig?: AxiosRequestConfig;
 };
 
 export class RuntimeClientFactory<S extends Record<string, any> = Record<string, any>> {
@@ -21,12 +23,12 @@ export class RuntimeClientFactory<S extends Record<string, any> = Record<string,
 
   private defaultState: State;
 
-  constructor({ versionID, endpoint = DEFAULT_ENDPOINT, dataConfig, variables }: FactoryConfig<S>) {
+  constructor({ versionID, endpoint = DEFAULT_ENDPOINT, dataConfig, variables, axiosConfig }: FactoryConfig<S>) {
     if (variables) {
       validateVarMerge(variables);
     }
 
-    this.client = new Client({ variables, endpoint, versionID });
+    this.client = new Client({ variables, endpoint, versionID, axiosConfig });
     this.defaultState = { stack: [], storage: {}, variables: { ...variables } };
 
     this.dataConfig = {
diff --git a/tests/lib/RuntimeClientFactory/index.unit.ts b/tests/lib/RuntimeClientFactory/index.unit.ts
index c117907..548c28c 100644
--- a/tests/lib/RuntimeClientFactory/index.unit.ts
+++ b/tests/lib/RuntimeClientFactory/index.unit.ts
@@ -32,19 +32,31 @@ describe('RuntimeClientFactory', () => {
     it('constructor', () => {
       const { client } = createRuntimeClientFactory();
 
-      expect(client.args).to.eql([[{ versionID: VERSION_ID, endpoint: DEFAULT_ENDPOINT, variables: undefined }]]);
+      expect(client.args).to.eql([[{ versionID: VERSION_ID, endpoint: DEFAULT_ENDPOINT, variables: undefined, axiosConfig: undefined }]]);
     });
 
     it('variables', () => {
       const { client } = createRuntimeClientFactory({ variables: 'foo' as any });
 
-      expect(client.args).to.eql([[{ versionID: VERSION_ID, endpoint: DEFAULT_ENDPOINT, variables: 'foo' }]]);
+      expect(client.args).to.eql([[{ versionID: VERSION_ID, endpoint: DEFAULT_ENDPOINT, variables: 'foo', axiosConfig: undefined }]]);
     });
 
-    it('optional', () => {
-      const { client } = createRuntimeClientFactory({ variables: 'foo' as any, versionID: 'bar', endpoint: 'x', dataConfig: 'y' as any });
+    it('axiosConfig', () => {
+      const { client } = createRuntimeClientFactory({ axiosConfig: 'foo' as any });
+
+      expect(client.args).to.eql([[{ versionID: VERSION_ID, endpoint: DEFAULT_ENDPOINT, variables: undefined, axiosConfig: 'foo' }]]);
+    });
 
-      expect(client.args).to.eql([[{ versionID: 'bar', endpoint: 'x', variables: 'foo' }]]);
+    it('optional', () => {
+      const { client } = createRuntimeClientFactory({
+        variables: 'foo' as any,
+        versionID: 'bar',
+        endpoint: 'x',
+        dataConfig: 'y' as any,
+        axiosConfig: 'bar' as any,
+      });
+
+      expect(client.args).to.eql([[{ versionID: 'bar', endpoint: 'x', variables: 'foo', axiosConfig: 'bar' }]]);
     });
 
     it('does not accept invalid variables', () => {