diff --git a/clang/lib/Format/WhitespaceManager.cpp b/clang/lib/Format/WhitespaceManager.cpp
--- a/clang/lib/Format/WhitespaceManager.cpp
+++ b/clang/lib/Format/WhitespaceManager.cpp
@@ -731,6 +731,11 @@
         if (&C != &Changes.back() && (&C + 1)->NewlinesBefore > 0)
           return false;
 
+        // Do not align operator= overloads.
+        FormatToken *Previous = C.Tok->getPreviousNonComment();
+        if (Previous && Previous->is(tok::kw_operator))
+          return false;
+
         return C.Tok->is(tok::equal);
       },
       Changes, /*StartAt=*/0, Style.AlignConsecutiveAssignments);
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
@@ -16266,6 +16266,34 @@
   verifyFormat("int oneTwoThree = 123; // comment\n"
                "int oneTwo      = 12;  // comment",
                Alignment);
+  verifyFormat("int f()         = default;\n"
+               "int &operator() = default;\n"
+               "int &operator=() {",
+               Alignment);
+  verifyFormat("int f()         = default; // comment\n"
+               "int &operator() = default; // comment\n"
+               "int &operator=() {",
+               Alignment);
+  verifyFormat("int f()         = default;\n"
+               "int &operator() = default;\n"
+               "int &operator==() {",
+               Alignment);
+  verifyFormat("int f()         = default;\n"
+               "int &operator() = default;\n"
+               "int &operator<=() {",
+               Alignment);
+  verifyFormat("int f()         = default;\n"
+               "int &operator() = default;\n"
+               "int &operator!=() {",
+               Alignment);
+  verifyFormat("int f()         = default;\n"
+               "int &operator() = default;\n"
+               "int &operator=();",
+               Alignment);
+  verifyFormat("/* long long padding */ int f() = default;\n"
+               "int &operator()                 = default;\n"
+               "int &operator/**/ =();",
+               Alignment);
 
   // Bug 25167
   /* Uncomment when fixed