diff --git a/.changeset/cool-bags-appear.md b/.changeset/cool-bags-appear.md
new file mode 100644
index 0000000000..f3c2e7fcc3
--- /dev/null
+++ b/.changeset/cool-bags-appear.md
@@ -0,0 +1,5 @@
+---
+'@backstage/core-components': patch
+---
+
+Provide a clearer error message when a authentication provider used by the `SignInPage` has not been configured to support sign-in.
diff --git a/packages/core-components/src/layout/SignInPage/SignInPage.tsx b/packages/core-components/src/layout/SignInPage/SignInPage.tsx
index d64a59158d..a7dc85c4e5 100644
--- a/packages/core-components/src/layout/SignInPage/SignInPage.tsx
+++ b/packages/core-components/src/layout/SignInPage/SignInPage.tsx
@@ -120,6 +120,11 @@ export const SingleSignInPage = ({
         identity = await authApi.getBackstageIdentity({
           instantPopup: true,
         });
+        if (!identity) {
+          throw new Error(
+            `The ${provider.title} provider is not configured to support sign-in`,
+          );
+        }
       }
 
       if (!identity) {
diff --git a/packages/core-components/src/layout/SignInPage/auth0Provider.tsx b/packages/core-components/src/layout/SignInPage/auth0Provider.tsx
index 518304d58c..78043cb3fb 100644
--- a/packages/core-components/src/layout/SignInPage/auth0Provider.tsx
+++ b/packages/core-components/src/layout/SignInPage/auth0Provider.tsx
@@ -33,6 +33,11 @@ const Component: ProviderComponent = ({ onResult }) => {
       const identity = await auth0AuthApi.getBackstageIdentity({
         instantPopup: true,
       });
+      if (!identity) {
+        throw new Error(
+          'The Auth0 provider is not configured to support sign-in',
+        );
+      }
 
       const profile = await auth0AuthApi.getProfile();
 
diff --git a/packages/core-components/src/layout/SignInPage/commonProvider.tsx b/packages/core-components/src/layout/SignInPage/commonProvider.tsx
index 0c5d195b1d..3160bd171b 100644
--- a/packages/core-components/src/layout/SignInPage/commonProvider.tsx
+++ b/packages/core-components/src/layout/SignInPage/commonProvider.tsx
@@ -36,6 +36,11 @@ const Component: ProviderComponent = ({ config, onResult }) => {
       const identity = await authApi.getBackstageIdentity({
         instantPopup: true,
       });
+      if (!identity) {
+        throw new Error(
+          `The ${title} provider is not configured to support sign-in`,
+        );
+      }
 
       const profile = await authApi.getProfile();
       onResult({