diff --git a/lib/std/fmt.zig b/lib/std/fmt.zig
index db4232ec0e..f3c43c5590 100644
--- a/lib/std/fmt.zig
+++ b/lib/std/fmt.zig
@@ -362,12 +362,21 @@ pub fn formatType(
             if (enumInfo.is_exhaustive) {
                 try out_stream.writeAll(".");
                 try out_stream.writeAll(@tagName(value));
-            } else {
-                // TODO: when @tagName works on exhaustive enums print known enum strings
-                try out_stream.writeAll("(");
-                try formatType(@enumToInt(value), fmt, options, out_stream, max_depth);
-                try out_stream.writeAll(")");
+                return;
             }
+
+            // Use @tagName only if value is one of known fields
+            inline for (enumInfo.fields) |enumField| {
+                if (@enumToInt(value) == enumField.value) {
+                    try out_stream.writeAll(".");
+                    try out_stream.writeAll(@tagName(value));
+                    return;
+                }
+            }
+
+            try out_stream.writeAll("(");
+            try formatType(@enumToInt(value), fmt, options, out_stream, max_depth);
+            try out_stream.writeAll(")");
         },
         .Union => {
             try out_stream.writeAll(@typeName(T));
@@ -1308,6 +1317,8 @@ test "enum" {
     const value = Enum.Two;
     try testFmt("enum: Enum.Two\n", "enum: {}\n", .{value});
     try testFmt("enum: Enum.Two\n", "enum: {}\n", .{&value});
+    try testFmt("enum: Enum.One\n", "enum: {x}\n", .{Enum.One});
+    try testFmt("enum: Enum.Two\n", "enum: {X}\n", .{Enum.Two});
 }
 
 test "non-exhaustive enum" {
@@ -1316,11 +1327,12 @@ test "non-exhaustive enum" {
         Two = 0xbeef,
         _,
     };
-    try testFmt("enum: Enum(15)\n", "enum: {}\n", .{Enum.One});
-    try testFmt("enum: Enum(48879)\n", "enum: {}\n", .{Enum.Two});
+    try testFmt("enum: Enum.One\n", "enum: {}\n", .{Enum.One});
+    try testFmt("enum: Enum.Two\n", "enum: {}\n", .{Enum.Two});
     try testFmt("enum: Enum(4660)\n", "enum: {}\n", .{@intToEnum(Enum, 0x1234)});
-    try testFmt("enum: Enum(f)\n", "enum: {x}\n", .{Enum.One});
-    try testFmt("enum: Enum(beef)\n", "enum: {x}\n", .{Enum.Two});
+    try testFmt("enum: Enum.One\n", "enum: {x}\n", .{Enum.One});
+    try testFmt("enum: Enum.Two\n", "enum: {x}\n", .{Enum.Two});
+    try testFmt("enum: Enum.Two\n", "enum: {X}\n", .{Enum.Two});
     try testFmt("enum: Enum(1234)\n", "enum: {x}\n", .{@intToEnum(Enum, 0x1234)});
 }