diff --git a/src/components/routingActions.js b/src/components/routingActions.js
index 507715de2..a86ad6ec7 100644
--- a/src/components/routingActions.js
+++ b/src/components/routingActions.js
@@ -1,14 +1,15 @@
 const validateActionArgs = func => {
-  return function (...args) {
+  return (...args) => {
     if (args.some(arg => typeof arg !== 'string')) throw new Error('Invalid redirect arguments');
     return func(...args);
   };
 };
 
 const ROUTES_MAP = {
-  stap: validateActionArgs(stepSlug => `stap/${stepSlug}`),
+  cosign: validateActionArgs(cosignAction => `cosign/${cosignAction}`),
   'afspraak-annuleren': validateActionArgs(() => 'afspraak-annuleren'),
-  cosign: cosignAction => validateActionArgs(`cosign/${cosignAction}`),
+  'afspraak-maken': validateActionArgs(() => `afspraak-maken`),
+  stap: validateActionArgs(stepSlug => `stap/${stepSlug}`),
 };
 
 export const getRedirectPathname = (action, actionArgs) => {
diff --git a/src/sdk.js b/src/sdk.js
index 7e41ac753..152964d7f 100644
--- a/src/sdk.js
+++ b/src/sdk.js
@@ -126,9 +126,9 @@ class OpenForm {
       const actionParams = query.get('_action_params');
       query.delete('_action');
       query.delete('_action_params');
-      const newUrl = `${document.location.origin}${this.basePath}/${
-        this.useHashRouting ? '#/' : ''
-      }${getRedirectPathname(action, actionParams)}?${query}`;
+      const newUrl = `${document.location.origin}${this.useHashRouting ? '/#' : ''}${
+        this.basePath
+      }/${getRedirectPathname(action, actionParams)}${query.size ? '?' + query : ''}`;
       window.history.replaceState(null, '', newUrl);
     }
 
diff --git a/src/sdk.spec.js b/src/sdk.spec.js
index e9e4e7d15..83aae83e9 100644
--- a/src/sdk.spec.js
+++ b/src/sdk.spec.js
@@ -125,7 +125,7 @@ describe('OpenForm', () => {
     expect(form.clientBaseUrl).toEqual('http://localhost/some-subpath');
   });
 
-  it('should correctly set the formUrl (hash fragment routing)', () => {
+  it('should correctly set the formUrl (hash based routing)', () => {
     mswServer.use(...apiMocks);
     window.history.pushState({}, 'Dummy title', '/some-server-side/path');
     const formRoot = document.createElement('div');
@@ -138,4 +138,76 @@ describe('OpenForm', () => {
 
     expect(form.clientBaseUrl).toEqual('http://localhost/some-server-side/path#/some-subpath');
   });
+
+  it.each([
+    [
+      '/some-subpath?_action=afspraak-annuleren',
+      'http://localhost/some-subpath/afspraak-annuleren',
+    ],
+    [
+      '/some-subpath?_action=afspraak-maken',
+      'http://localhost/some-subpath/afspraak-maken/producten',
+    ],
+    [
+      '/some-subpath?_action=cosign&_action_params=check',
+      'http://localhost/some-subpath/cosign/check',
+    ],
+    [
+      '/some-subpath?_action=stap&_action_params=step-1',
+      'http://localhost/some-subpath/stap/step-1',
+    ],
+  ])('should handle action redirects correctly', async (initialUrl, expected) => {
+    mswServer.use(...apiMocks);
+    const formRoot = document.createElement('div');
+    window.history.pushState(null, '', initialUrl);
+    const form = new OpenForm(formRoot, {
+      baseUrl: BASE_URL,
+      basePath: '/some-subpath',
+      formId: '81a22589-abce-4147-a2a3-62e9a56685aa',
+      lang: 'nl',
+    });
+    await act(async () => await form.init());
+
+    // wait for the loader to be removed when all network requests have completed
+    await waitForElementToBeRemoved(() => within(formRoot).getByRole('status'));
+    expect(location.href).toEqual(expected);
+  });
+
+  it.each([
+    [
+      '/some-subpath?_action=afspraak-annuleren',
+      'http://localhost/#/some-subpath/afspraak-annuleren',
+    ],
+    [
+      '/some-subpath?_action=afspraak-maken',
+      'http://localhost/#/some-subpath/afspraak-maken/producten',
+    ],
+    [
+      '/some-subpath?_action=cosign&_action_params=check',
+      'http://localhost/#/some-subpath/cosign/check',
+    ],
+    [
+      '/some-subpath?_action=stap&_action_params=step-1',
+      'http://localhost/#/some-subpath/stap/step-1',
+    ],
+  ])(
+    'should handle action redirects correctly (hash based routing)',
+    async (initialUrl, expected) => {
+      mswServer.use(...apiMocks);
+      const formRoot = document.createElement('div');
+      window.history.pushState(null, '', initialUrl);
+      const form = new OpenForm(formRoot, {
+        baseUrl: BASE_URL,
+        basePath: '/some-subpath',
+        formId: '81a22589-abce-4147-a2a3-62e9a56685aa',
+        useHashRouting: true,
+        lang: 'nl',
+      });
+      await act(async () => await form.init());
+
+      // wait for the loader to be removed when all network requests have completed
+      await waitForElementToBeRemoved(() => within(formRoot).getByRole('status'));
+      expect(location.href).toEqual(expected);
+    }
+  );
 });