diff --git a/clang/lib/Format/Format.cpp b/clang/lib/Format/Format.cpp
--- a/clang/lib/Format/Format.cpp
+++ b/clang/lib/Format/Format.cpp
@@ -1898,8 +1898,9 @@
         assert(Token->isOneOf(tok::l_brace, tok::r_brace));
         assert(Token->Next || Token == Line->Last);
         const auto Start =
-            Token == Line->Last || (Token->Next->is(tok::kw_else) &&
-                                    Token->Next->NewlinesBefore > 0)
+            Token == Line->Last ||
+                    (Token->Next->isOneOf(tok::kw_else, tok::comment) &&
+                     Token->Next->NewlinesBefore > 0)
                 ? Token->WhitespaceRange.getBegin()
                 : Token->Tok.getLocation();
         const auto Range =
diff --git a/clang/unittests/Format/FormatTest.cpp b/clang/unittests/Format/FormatTest.cpp
--- a/clang/unittests/Format/FormatTest.cpp
+++ b/clang/unittests/Format/FormatTest.cpp
@@ -25348,6 +25348,20 @@
                "}",
                Style);
 
+  verifyFormat("if (a)\n"
+               "  foo();\n"
+               "// comment\n"
+               "else\n"
+               "  bar();",
+               "if (a) {\n"
+               "  foo();\n"
+               "}\n"
+               "// comment\n"
+               "else {\n"
+               "  bar();\n"
+               "}",
+               Style);
+
   verifyFormat("if (a) {\n"
                "Label:\n"
                "}",