diff --git a/.changeset/eleven-lamps-hide.md b/.changeset/eleven-lamps-hide.md
new file mode 100644
index 0000000000..809de25c82
--- /dev/null
+++ b/.changeset/eleven-lamps-hide.md
@@ -0,0 +1,5 @@
+---
+'@backstage/integration': patch
+---
+
+Fix default branch API url for custom hosted Bitbucket server
diff --git a/packages/backend-common/src/reading/BitbucketUrlReader.test.ts b/packages/backend-common/src/reading/BitbucketUrlReader.test.ts
index 9661368b5e..6265718571 100644
--- a/packages/backend-common/src/reading/BitbucketUrlReader.test.ts
+++ b/packages/backend-common/src/reading/BitbucketUrlReader.test.ts
@@ -126,12 +126,12 @@ describe('BitbucketUrlReader', () => {
             ),
         ),
         rest.get(
-          'https://api.bitbucket.mycompany.net/rest/api/1.0/repositories/backstage/mock/commits/some-branch',
+          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/commits',
           (_, res, ctx) =>
             res(
               ctx.status(200),
               ctx.json({
-                values: [{ hash: '12ab34cd56ef78gh90ij12kl34mn56op78qr90st' }],
+                values: [{ id: '12ab34cd56ef78gh90ij12kl34mn56op78qr90st' }],
               }),
             ),
         ),
diff --git a/packages/backend-common/src/reading/BitbucketUrlReader.ts b/packages/backend-common/src/reading/BitbucketUrlReader.ts
index e9727e04cf..86dd7e32b0 100644
--- a/packages/backend-common/src/reading/BitbucketUrlReader.ts
+++ b/packages/backend-common/src/reading/BitbucketUrlReader.ts
@@ -161,13 +161,18 @@ export class BitbucketUrlReader implements UrlReader {
   }
 
   private async getLastCommitShortHash(url: string): Promise<string> {
-    const { name: repoName, owner: project, ref } = parseGitUrl(url);
+    const { resource, name: repoName, owner: project, ref } = parseGitUrl(url);
 
     let branch = ref;
     if (!branch) {
       branch = await getBitbucketDefaultBranch(url, this.config);
     }
-    const commitsApiUrl = `${this.config.apiBaseUrl}/repositories/${project}/${repoName}/commits/${branch}`;
+
+    const isHosted = resource === 'bitbucket.org';
+    // Bitbucket Server https://docs.atlassian.com/bitbucket-server/rest/7.9.0/bitbucket-rest.html#idp222
+    const commitsApiUrl = isHosted
+      ? `${this.config.apiBaseUrl}/repositories/${project}/${repoName}/commits/${branch}`
+      : `${this.config.apiBaseUrl}/projects/${project}/repos/${repoName}/commits`;
 
     const commitsResponse = await fetch(
       commitsApiUrl,
@@ -182,14 +187,26 @@ export class BitbucketUrlReader implements UrlReader {
     }
 
     const commits = await commitsResponse.json();
-    if (
-      commits &&
-      commits.values &&
-      commits.values.length > 0 &&
-      commits.values[0].hash
-    ) {
-      return commits.values[0].hash.substring(0, 12);
+    if (isHosted) {
+      if (
+        commits &&
+        commits.values &&
+        commits.values.length > 0 &&
+        commits.values[0].hash
+      ) {
+        return commits.values[0].hash.substring(0, 12);
+      }
+    } else {
+      if (
+        commits &&
+        commits.values &&
+        commits.values.length > 0 &&
+        commits.values[0].id
+      ) {
+        return commits.values[0].id.substring(0, 12);
+      }
     }
+
     throw new Error(`Failed to read response from ${commitsApiUrl}`);
   }
 }
diff --git a/packages/integration/src/bitbucket/core.test.ts b/packages/integration/src/bitbucket/core.test.ts
index 39707976fe..1287ab4d66 100644
--- a/packages/integration/src/bitbucket/core.test.ts
+++ b/packages/integration/src/bitbucket/core.test.ts
@@ -116,7 +116,7 @@ describe('bitbucket core', () => {
       };
       worker.use(
         rest.get(
-          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/branches/default',
+          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/default-branch',
           (_, res, ctx) =>
             res(
               ctx.status(200),
@@ -144,7 +144,7 @@ describe('bitbucket core', () => {
       };
       worker.use(
         rest.get(
-          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/branches/default',
+          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/default-branch',
           (_, res, ctx) =>
             res(
               ctx.status(200),
@@ -231,7 +231,7 @@ describe('bitbucket core', () => {
       };
       worker.use(
         rest.get(
-          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/branches/default',
+          'https://api.bitbucket.mycompany.net/rest/api/1.0/projects/backstage/repos/mock/default-branch',
           (_, res, ctx) =>
             res(
               ctx.status(200),
diff --git a/packages/integration/src/bitbucket/core.ts b/packages/integration/src/bitbucket/core.ts
index ae61df497d..f5235d8189 100644
--- a/packages/integration/src/bitbucket/core.ts
+++ b/packages/integration/src/bitbucket/core.ts
@@ -31,9 +31,10 @@ export async function getBitbucketDefaultBranch(
   const { name: repoName, owner: project, resource } = parseGitUrl(url);
 
   const isHosted = resource === 'bitbucket.org';
+  // Bitbucket Server https://docs.atlassian.com/bitbucket-server/rest/7.9.0/bitbucket-rest.html#idp184
   const branchUrl = isHosted
     ? `${config.apiBaseUrl}/repositories/${project}/${repoName}`
-    : `${config.apiBaseUrl}/projects/${project}/repos/${repoName}/branches/default`;
+    : `${config.apiBaseUrl}/projects/${project}/repos/${repoName}/default-branch`;
 
   const response = await fetch(branchUrl, getBitbucketRequestOptions(config));
   if (!response.ok) {
@@ -50,7 +51,10 @@ export async function getBitbucketDefaultBranch(
     defaultBranch = displayId;
   }
   if (!defaultBranch) {
-    throw new Error(`Failed to read default branch from ${branchUrl}`);
+    throw new Error(
+      `Failed to read default branch from ${branchUrl}. ` +
+        `Response ${response.status} ${response.json()}`,
+    );
   }
   return defaultBranch;
 }