diff --git a/dist/index.js b/dist/index.js
index 8258ff1..84fd382 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -13755,7 +13755,14 @@ let BASE_SHA;
         process.stdout.write('\n');
         process.stdout.write(`NOTE: You can instead make this a hard error by setting 'error-on-no-successful-workflow' on the action in your workflow.\n`);
 
-        BASE_SHA = execSync(`git rev-parse origin/${mainBranchName}~1`, { encoding: 'utf-8' });
+        let getBaseShaCommand = `git rev-parse origin/${mainBranchName}`;
+        const commitCountOutput = execSync(`git rev-list --count origin/${mainBranchName}`, { encoding: 'utf-8' });
+        const commitCount = parseInt(stripNewLineEndings(commitCountOutput), 10);
+        if (commitCount > 1) {
+          getBaseShaCommand = `${getBaseShaCommand}~1`;
+        }
+
+        BASE_SHA = execSync(getBaseShaCommand, { encoding: 'utf-8' });
         core.setOutput('noPreviousBuild', 'true');
       }
     } else {
@@ -13763,9 +13770,8 @@ let BASE_SHA;
       process.stdout.write(`Found the last successful workflow run on 'origin/${mainBranchName}'\n`);
       process.stdout.write(`Commit: ${BASE_SHA}\n`);
     }
-  }
 
-  const stripNewLineEndings = sha => sha.replace('\n', '');
+  }
   core.setOutput('base', stripNewLineEndings(BASE_SHA));
   core.setOutput('head', stripNewLineEndings(HEAD_SHA));
 })();
@@ -13843,6 +13849,13 @@ async function commitExists(commitSha) {
   }
 }
 
+/**
+ * Strips LF line endings from given string
+ * @param {string} string
+ */
+function stripNewLineEndings(string) {
+  return string.replace('\n', '');
+}
 })();
 
 module.exports = __webpack_exports__;
diff --git a/find-successful-workflow.js b/find-successful-workflow.js
index bc1181f..1d04418 100644
--- a/find-successful-workflow.js
+++ b/find-successful-workflow.js
@@ -47,7 +47,14 @@ let BASE_SHA;
         process.stdout.write('\n');
         process.stdout.write(`NOTE: You can instead make this a hard error by setting 'error-on-no-successful-workflow' on the action in your workflow.\n`);
 
-        BASE_SHA = execSync(`git rev-parse origin/${mainBranchName}~1`, { encoding: 'utf-8' });
+        let getBaseShaCommand = `git rev-parse origin/${mainBranchName}`;
+        const commitCountOutput = execSync(`git rev-list --count origin/${mainBranchName}`, { encoding: 'utf-8' });
+        const commitCount = parseInt(stripNewLineEndings(commitCountOutput), 10);
+        if (commitCount > 1) {
+          getBaseShaCommand = `${getBaseShaCommand}~1`;
+        }
+
+        BASE_SHA = execSync(getBaseShaCommand, { encoding: 'utf-8' });
         core.setOutput('noPreviousBuild', 'true');
       }
     } else {
@@ -55,9 +62,8 @@ let BASE_SHA;
       process.stdout.write(`Found the last successful workflow run on 'origin/${mainBranchName}'\n`);
       process.stdout.write(`Commit: ${BASE_SHA}\n`);
     }
-  }
 
-  const stripNewLineEndings = sha => sha.replace('\n', '');
+  }
   core.setOutput('base', stripNewLineEndings(BASE_SHA));
   core.setOutput('head', stripNewLineEndings(HEAD_SHA));
 })();
@@ -134,3 +140,11 @@ async function commitExists(commitSha) {
     return false;
   }
 }
+
+/**
+ * Strips LF line endings from given string
+ * @param {string} string
+ */
+function stripNewLineEndings(string) {
+  return string.replace('\n', '');
+}
\ No newline at end of file