diff --git a/packages/ajax/src/interceptors/cacheInterceptors.js b/packages/ajax/src/interceptors/cacheInterceptors.js
index 06686dc76..1cb33883d 100644
--- a/packages/ajax/src/interceptors/cacheInterceptors.js
+++ b/packages/ajax/src/interceptors/cacheInterceptors.js
@@ -31,10 +31,10 @@ const isMethodSupported = (methods, method) => methods.includes(method.toLowerCa
  * @param {string[]|undefined} contentTypes
  * @returns {boolean} `true` if the contentTypes property is not an array, or if the value of the Content-Type header is in the array
  */
-const isResponseContentTypeSupported = (response, contentTypes) => {
+export const isResponseContentTypeSupported = (response, contentTypes) => {
   if (!Array.isArray(contentTypes)) return true;
 
-  return contentTypes.includes(String(response.headers.get('Content-Type')));
+  return !!contentTypes.find(ct => String(response.headers.get('Content-Type')).includes(ct));
 };
 
 /**
diff --git a/packages/ajax/test/interceptors/cacheInterceptors.test.js b/packages/ajax/test/interceptors/cacheInterceptors.test.js
index 6c9e43eb6..2d6862c2d 100644
--- a/packages/ajax/test/interceptors/cacheInterceptors.test.js
+++ b/packages/ajax/test/interceptors/cacheInterceptors.test.js
@@ -1,6 +1,7 @@
 import { expect } from '@open-wc/testing';
 import * as sinon from 'sinon';
 import { Ajax, createCacheInterceptors } from '@lion/ajax';
+import { isResponseContentTypeSupported } from '../../src/interceptors/cacheInterceptors.js';
 
 // TODO: these are private API? should they be exposed? if not why do we test them?
 import { extendCacheOptions, resetCacheSession, ajaxCache } from '../../src/cacheManager.js';
@@ -72,6 +73,36 @@ describe('cache interceptors', () => {
     sinon.restore();
   });
 
+  describe('isResponseContentTypeSupported', () => {
+    /** @type {Response} */
+    let r;
+
+    beforeEach(() => {
+      r = new Response('');
+    });
+
+    it('matches default content type', () => {
+      r.headers.set('Content-Type', 'application/json');
+      expect(isResponseContentTypeSupported(r, ['application/json'])).to.equal(true);
+    });
+
+    it('returns false when it doesnt match', () => {
+      r.headers.set('Content-Type', 'text/json');
+      expect(isResponseContentTypeSupported(r, ['application/json'])).to.equal(false);
+    });
+
+    it('partially matches content type', () => {
+      r.headers.set('Content-Type', 'text/plain;charset=UTF-8;');
+      expect(isResponseContentTypeSupported(r, ['text/plain'])).to.equal(true);
+    });
+
+    it('returns true if `contentTypes` is not an array', () => {
+      r.headers.set('Content-Type', 'foo');
+      // @ts-ignore needed for test
+      expect(isResponseContentTypeSupported(r, 'string')).to.equal(true);
+    });
+  });
+
   describe('Original ajax instance', () => {
     it('allows direct ajax calls without cache interceptors configured', async () => {
       await ajax.fetch('/test');