diff --git a/src/Standards/Generic/Sniffs/WhiteSpace/DisallowTabIndentSniff.php b/src/Standards/Generic/Sniffs/WhiteSpace/DisallowTabIndentSniff.php
index e230916ca3..ecf19ca53f 100644
--- a/src/Standards/Generic/Sniffs/WhiteSpace/DisallowTabIndentSniff.php
+++ b/src/Standards/Generic/Sniffs/WhiteSpace/DisallowTabIndentSniff.php
@@ -169,6 +169,14 @@ public function process(File $phpcsFile, $stackPtr)
                 continue;
             }
 
+            // Report, but don't auto-fix tab identation for a PHP 7.3+ flexible heredoc/nowdoc closer.
+            // Auto-fixing this would cause parse errors as the indentation of the heredoc/nowdoc contents
+            // needs to use the same type of indentation. Also see: https://3v4l.org/7OF3M .
+            if ($tokens[$i]['code'] === T_END_HEREDOC || $tokens[$i]['code'] === T_END_NOWDOC) {
+                $phpcsFile->addError($error, $i, $errorCode.'HeredocCloser');
+                continue;
+            }
+
             $fix = $phpcsFile->addFixableError($error, $i, $errorCode);
             if ($fix === true) {
                 if (isset($tokens[$i]['orig_content']) === true) {
diff --git a/src/Standards/Generic/Tests/WhiteSpace/DisallowTabIndentUnitTest.3.inc.fixed b/src/Standards/Generic/Tests/WhiteSpace/DisallowTabIndentUnitTest.3.inc.fixed
deleted file mode 100644
index 622088ad29..0000000000
--- a/src/Standards/Generic/Tests/WhiteSpace/DisallowTabIndentUnitTest.3.inc.fixed
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-$heredoc = <<<"END"
-		a
-		b
-		c
-    END;
-
-$nowdoc = <<<'END'
-		a
-		b
-		c
-    END;