diff --git a/lib/platform/bitbucket/index.ts b/lib/platform/bitbucket/index.ts
index 9a9ee675622e9f8eeee73c0d1efe0b5fab9be268..acb30e8f017c8fc5e075e6b6c72bf281a14552a8 100644
--- a/lib/platform/bitbucket/index.ts
+++ b/lib/platform/bitbucket/index.ts
@@ -592,19 +592,16 @@ export async function getPr(prNo: number) {
     // TODO: Is that correct? Should we check getBranchStatus like gitlab?
     res.canMerge = !res.isConflicted;
 
-    // we only want the first commit, because size tells us the overall number
-    const { body } = await api.get<utils.PagedResult<Commit>>(
-      pr.links.commits.href + '?pagelen=1'
-    );
+    // we only want the first two commits, because size tells us the overall number
+    const url = pr.links.commits.href + '?pagelen=2';
+    const { body } = await api.get<utils.PagedResult<Commit>>(url);
+    const size = body.size || body.values.length;
 
     // istanbul ignore if
-    if (body.size === undefined) {
-      logger.warn(
-        { prNo, url: pr.links.commits.href + '?pagelen=1', body },
-        'invalid response so can rebase'
-      );
+    if (size === undefined) {
+      logger.warn({ prNo, url, body }, 'invalid response so can rebase');
       pr.canRebase = true;
-    } else if (body.size === 1) {
+    } else if (size === 1) {
       if (global.gitAuthor) {
         const author = addrs.parseOneAddress(
           body.values[0].author.raw
@@ -630,7 +627,7 @@ export async function getPr(prNo: number) {
         pr.canRebase = true;
       }
     } else {
-      logger.debug({ prNo }, `${body.size} commits so cannot rebase`);
+      logger.debug({ prNo }, `${size} commits so cannot rebase`);
       pr.canRebase = false;
     }
   }
diff --git a/lib/platform/bitbucket/utils.ts b/lib/platform/bitbucket/utils.ts
index a9b214a9b49859a62dffeeb715ad5cd44b908b41..4b087591b50273701adc02c50a8ab9a6a9288690 100644
--- a/lib/platform/bitbucket/utils.ts
+++ b/lib/platform/bitbucket/utils.ts
@@ -19,7 +19,8 @@ export interface Config {
 }
 
 export interface PagedResult<T = any> {
-  size: number;
+  pagelen: number;
+  size?: number;
   next?: string;
   values: T[];
 }
diff --git a/test/platform/bitbucket/__snapshots__/index.spec.ts.snap b/test/platform/bitbucket/__snapshots__/index.spec.ts.snap
index 2eda4163f07e9fccc76af8b3196763feade457fd..43a5c359ecd40f1fd04c613d8053046346c9743d 100644
--- a/test/platform/bitbucket/__snapshots__/index.spec.ts.snap
+++ b/test/platform/bitbucket/__snapshots__/index.spec.ts.snap
@@ -214,7 +214,7 @@ Array [
     },
   ],
   Array [
-    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/3/commits?pagelen=1",
+    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/3/commits?pagelen=2",
   ],
   Array [
     "/2.0/repositories/some/repo/pullrequests/5",
@@ -226,7 +226,7 @@ Array [
     },
   ],
   Array [
-    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/5/commits?pagelen=1",
+    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/5/commits?pagelen=2",
   ],
   Array [
     "/2.0/repositories/some/repo/pullrequests/5",
@@ -238,7 +238,7 @@ Array [
     },
   ],
   Array [
-    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/5/commits?pagelen=1",
+    "https://api.bitbucket.org/2.0/repositories/some/repo/pullrequests/5/commits?pagelen=2",
   ],
 ]
 `;