diff --git a/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.test.tsx b/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.test.tsx
index 4352a3a6b8248e..2e17153ee34e75 100644
--- a/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.test.tsx
+++ b/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.test.tsx
@@ -142,6 +142,13 @@ describe('Output form validation', () => {
 
       expect(res).toBeUndefined();
     });
+
+    it('should work with hostnames using uppercase letters', () => {
+      const res = validateLogstashHosts(['tEsT.fr:9200', 'TEST2.fr:9200', 'teSt.fR:9999']);
+
+      expect(res).toBeUndefined();
+    });
+
     it('should throw for invalid hosts starting with http', () => {
       const res = validateLogstashHosts(['https://test.fr:5044']);
 
diff --git a/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.tsx b/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.tsx
index 330d5c5d201224..116e9f4abf1579 100644
--- a/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.tsx
+++ b/x-pack/plugins/fleet/public/applications/fleet/sections/settings/components/edit_output_flyout/output_form_validators.tsx
@@ -166,7 +166,7 @@ export function validateLogstashHosts(value: string[]) {
 
       const url = new URL(`http://${val}`);
 
-      if (url.host !== val) {
+      if (url.host !== val.toLowerCase()) {
         throw new Error('Invalid host');
       }
     } catch (error) {
diff --git a/x-pack/plugins/fleet/server/types/models/output.test.ts b/x-pack/plugins/fleet/server/types/models/output.test.ts
index 06edd900fec2a8..9c850766b9ba82 100644
--- a/x-pack/plugins/fleet/server/types/models/output.test.ts
+++ b/x-pack/plugins/fleet/server/types/models/output.test.ts
@@ -13,6 +13,10 @@ describe('Output model', () => {
       expect(validateLogstashHost('test.fr:5044')).toBeUndefined();
     });
 
+    it('should support valid host with uppercase letters', () => {
+      expect(validateLogstashHost('tEsT.fr:5044')).toBeUndefined();
+    });
+
     it('should return an error for an invalid host', () => {
       expect(validateLogstashHost('!@#%&!#!@')).toMatchInlineSnapshot(`"Invalid Logstash host"`);
     });
diff --git a/x-pack/plugins/fleet/server/types/models/output.ts b/x-pack/plugins/fleet/server/types/models/output.ts
index 730ec512f5a0fb..765018f3ac88f6 100644
--- a/x-pack/plugins/fleet/server/types/models/output.ts
+++ b/x-pack/plugins/fleet/server/types/models/output.ts
@@ -26,7 +26,7 @@ export function validateLogstashHost(val: string) {
   try {
     const url = new URL(`http://${val}`);
 
-    if (url.host !== val) {
+    if (url.host !== val.toLowerCase()) {
       return 'Invalid host';
     }
   } catch (err) {