diff --git a/packages/core/__tests__/core.test.ts b/packages/core/__tests__/core.test.ts
index 0e52e9b2cf..17547c3a96 100644
--- a/packages/core/__tests__/core.test.ts
+++ b/packages/core/__tests__/core.test.ts
@@ -159,17 +159,17 @@ describe('@actions/core', () => {
 
   it('setOutput produces the correct command', () => {
     core.setOutput('some output', 'some value')
-    assertWriteCalls([`::set-output name=some output::some value${os.EOL}`])
+    assertWriteCalls([os.EOL, `::set-output name=some output::some value${os.EOL}`])
   })
 
   it('setOutput handles bools', () => {
     core.setOutput('some output', false)
-    assertWriteCalls([`::set-output name=some output::false${os.EOL}`])
+    assertWriteCalls([os.EOL, `::set-output name=some output::false${os.EOL}`])
   })
 
   it('setOutput handles numbers', () => {
     core.setOutput('some output', 1.01)
-    assertWriteCalls([`::set-output name=some output::1.01${os.EOL}`])
+    assertWriteCalls([os.EOL, `::set-output name=some output::1.01${os.EOL}`])
   })
 
   it('setFailed sets the correct exit code and failure message', () => {
diff --git a/packages/core/src/core.ts b/packages/core/src/core.ts
index e7e366c501..13f4dfa3f0 100644
--- a/packages/core/src/core.ts
+++ b/packages/core/src/core.ts
@@ -99,6 +99,7 @@ export function getInput(name: string, options?: InputOptions): string {
  */
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 export function setOutput(name: string, value: any): void {
+  process.stdout.write(os.EOL)
   issueCommand('set-output', {name}, value)
 }