diff --git a/src/Command/AnalyseCommand.php b/src/Command/AnalyseCommand.php
index c7c3e9f8aba..72b16060ad2 100644
--- a/src/Command/AnalyseCommand.php
+++ b/src/Command/AnalyseCommand.php
@@ -11,6 +11,7 @@
 use PHPStan\Command\Symfony\SymfonyOutput;
 use PHPStan\Command\Symfony\SymfonyStyle;
 use PHPStan\File\CouldNotWriteFileException;
+use PHPStan\File\FileReader;
 use PHPStan\File\FileWriter;
 use PHPStan\File\ParentDirectoryRelativePathHelper;
 use PHPStan\File\PathNotFoundException;
@@ -32,6 +33,7 @@
 use function is_array;
 use function is_bool;
 use function is_dir;
+use function is_file;
 use function is_string;
 use function mkdir;
 use function pathinfo;
@@ -279,10 +281,12 @@ protected function execute(InputInterface $input, OutputInterface $output): int
 			$baselineFileDirectory = dirname($generateBaselineFile);
 			$baselineErrorFormatter = new BaselineNeonErrorFormatter(new ParentDirectoryRelativePathHelper($baselineFileDirectory));
 
+			$existingBaselineContent = is_file($generateBaselineFile) ? FileReader::read($generateBaselineFile) : '';
+
 			$streamOutput = $this->createStreamOutput();
 			$errorConsoleStyle = new ErrorsConsoleStyle(new StringInput(''), $streamOutput);
 			$baselineOutput = new SymfonyOutput($streamOutput, new SymfonyStyle($errorConsoleStyle));
-			$baselineErrorFormatter->formatErrors($analysisResult, $baselineOutput);
+			$baselineErrorFormatter->formatErrors($analysisResult, $baselineOutput, $existingBaselineContent);
 
 			$stream = $streamOutput->getStream();
 			rewind($stream);
diff --git a/src/Command/ErrorFormatter/BaselineNeonErrorFormatter.php b/src/Command/ErrorFormatter/BaselineNeonErrorFormatter.php
index 83cc9a13c0d..545eeed111c 100644
--- a/src/Command/ErrorFormatter/BaselineNeonErrorFormatter.php
+++ b/src/Command/ErrorFormatter/BaselineNeonErrorFormatter.php
@@ -4,6 +4,7 @@
 
 use Nette\DI\Helpers;
 use Nette\Neon\Neon;
+use Nette\Utils\Strings;
 use PHPStan\Command\AnalysisResult;
 use PHPStan\Command\Output;
 use PHPStan\File\RelativePathHelper;
@@ -23,10 +24,11 @@ public function __construct(private RelativePathHelper $relativePathHelper)
 	public function formatErrors(
 		AnalysisResult $analysisResult,
 		Output $output,
+		string $existingBaselineContent,
 	): int
 	{
 		if (!$analysisResult->hasErrors()) {
-			$output->writeRaw($this->getNeon([]));
+			$output->writeRaw($this->getNeon([], $existingBaselineContent));
 			return 0;
 		}
 
@@ -61,7 +63,7 @@ public function formatErrors(
 			}
 		}
 
-		$output->writeRaw($this->getNeon($errorsToOutput));
+		$output->writeRaw($this->getNeon($errorsToOutput, $existingBaselineContent));
 
 		return 1;
 	}
@@ -69,7 +71,7 @@ public function formatErrors(
 	/**
 	 * @param array<int, array{message: string, count: int, path: string}> $ignoreErrors
 	 */
-	private function getNeon(array $ignoreErrors): string
+	private function getNeon(array $ignoreErrors, string $existingBaselineContent): string
 	{
 		$neon = Neon::encode([
 			'parameters' => [
@@ -81,7 +83,16 @@ private function getNeon(array $ignoreErrors): string
 			throw new ShouldNotHappenException();
 		}
 
-		return substr($neon, 0, -1);
+		if ($existingBaselineContent === '') {
+			return substr($neon, 0, -1);
+		}
+
+		$existingBaselineContentEndOfFileNewlinesMatches = Strings::match($existingBaselineContent, "~(\n)+$~");
+		$existingBaselineContentEndOfFileNewlines = $existingBaselineContentEndOfFileNewlinesMatches !== null
+			? $existingBaselineContentEndOfFileNewlinesMatches[0]
+			: '';
+
+		return substr($neon, 0, -2) . $existingBaselineContentEndOfFileNewlines;
 	}
 
 }
diff --git a/tests/PHPStan/Command/ErrorFormatter/BaselineNeonErrorFormatterTest.php b/tests/PHPStan/Command/ErrorFormatter/BaselineNeonErrorFormatterTest.php
index 7cbcb7adb9e..e6e23f8e46e 100644
--- a/tests/PHPStan/Command/ErrorFormatter/BaselineNeonErrorFormatterTest.php
+++ b/tests/PHPStan/Command/ErrorFormatter/BaselineNeonErrorFormatterTest.php
@@ -128,6 +128,7 @@ public function testFormatErrors(
 		$this->assertSame($exitCode, $formatter->formatErrors(
 			$this->getAnalysisResult($numFileErrors, $numGenericErrors),
 			$this->getOutput(),
+			''
 		), sprintf('%s: response code do not match', $message));
 
 		$this->assertSame(trim(Neon::encode(['parameters' => ['ignoreErrors' => $expected]], Neon::BLOCK)), trim($this->getOutputContent()), sprintf('%s: output do not match', $message));
@@ -150,6 +151,7 @@ public function testFormatErrorMessagesRegexEscape(): void
 		$formatter->formatErrors(
 			$result,
 			$this->getOutput(),
+			''
 		);
 
 		self::assertSame(
@@ -186,6 +188,7 @@ public function testEscapeDiNeon(): void
 		$formatter->formatErrors(
 			$result,
 			$this->getOutput(),
+			''
 		);
 		self::assertSame(
 			trim(
@@ -248,6 +251,7 @@ public function testOutputOrdering(array $errors): void
 		$formatter->formatErrors(
 			$result,
 			$this->getOutput(),
+			''
 		);
 		self::assertSame(
 			trim(Neon::encode([
@@ -300,14 +304,63 @@ public function testOutputOrdering(array $errors): void
 	 */
 	public function endOfFileNewlinesProvider(): Generator
 	{
+		$existingBaselineContentWithoutEndNewlines = 'parameters:
+	ignoreErrors:
+		-
+			message: "#^Existing error$#"
+			count: 1
+			path: TestfileA';
+
 		yield 'one error' => [
 			'errors' => [
 				new Error('Error #1', 'TestfileA', 1),
 			],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines . "\n",
+			'expectedNewlinesCount' => 1,
 		];
 
 		yield 'no errors' => [
 			'errors' => [],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines . "\n",
+			'expectedNewlinesCount' => 1,
+		];
+
+		yield 'one error with 2 newlines' => [
+			'errors' => [
+				new Error('Error #1', 'TestfileA', 1),
+			],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines . "\n\n",
+			'expectedNewlinesCount' => 2,
+		];
+
+		yield 'no errors with 2 newlines' => [
+			'errors' => [],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines . "\n\n",
+			'expectedNewlinesCount' => 2,
+		];
+
+		yield 'one error with 0 newlines' => [
+			'errors' => [
+				new Error('Error #1', 'TestfileA', 1),
+			],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines,
+			'expectedNewlinesCount' => 0,
+		];
+
+		yield 'one error with 3 newlines' => [
+			'errors' => [
+				new Error('Error #1', 'TestfileA', 1),
+			],
+			'existingBaselineContent' => $existingBaselineContentWithoutEndNewlines . "\n\n\n",
+			'expectedNewlinesCount' => 3,
+		];
+
+		yield 'empty existing baseline' => [
+			'errors' => [
+				new Error('Error #1', 'TestfileA', 1),
+			],
+			'existingBaselineContent' => '',
+			'expectedNewlinesCount' => 1,
 		];
 	}
 
@@ -316,7 +369,11 @@ public function endOfFileNewlinesProvider(): Generator
 	 *
 	 * @param list<Error> $errors
 	 */
-	public function testEndOfFileNewlines(array $errors): void
+	public function testEndOfFileNewlines(
+		array $errors,
+		string $existingBaselineContent,
+		int $expectedNewlinesCount,
+	): void
 	{
 		$formatter = new BaselineNeonErrorFormatter(new SimpleRelativePathHelper(self::DIRECTORY_PATH));
 		$result = new AnalysisResult(
@@ -341,6 +398,7 @@ public function testEndOfFileNewlines(array $errors): void
 		$formatter->formatErrors(
 			$result,
 			$output,
+			$existingBaselineContent
 		);
 
 		rewind($outputStream->getStream());
@@ -350,8 +408,10 @@ public function testEndOfFileNewlines(array $errors): void
 			throw new ShouldNotHappenException();
 		}
 
-		Assert::assertSame("\n", substr($content, -1));
-		Assert::assertNotSame("\n", substr($content, -2, 1));
+		if ($expectedNewlinesCount > 0) {
+			Assert::assertSame(str_repeat("\n", $expectedNewlinesCount), substr($content, -$expectedNewlinesCount));
+		}
+		Assert::assertNotSame("\n", substr($content, -($expectedNewlinesCount + 1), 1));
 	}
 
 }