diff --git a/handler.go b/handler.go
index d431628..61049fd 100644
--- a/handler.go
+++ b/handler.go
@@ -14,6 +14,8 @@ const (
 	nameKey = "$name"
 	// stackKey is the key for the logger stack attribute
 	stackKey = "$stack"
+	// errorKey is the key for the logger error attribute
+	errorKey = "$err"
 	// msgKey is the key for the logger message attribute
 	msgKey = "$msg"
 	// timeKey is the key for the logger time attribute
diff --git a/logger.go b/logger.go
index 3704e8c..8566fcb 100644
--- a/logger.go
+++ b/logger.go
@@ -97,6 +97,10 @@ func (l *Logger) log(ctx context.Context, level slog.Level, err error, msg strin
 	if err != nil && config.EnableStackTrace {
 		r.Add(stackKey, fmt.Sprintf("%+v", err))
 	}
+	// add error if not nil
+	if err != nil {
+		r.Add(errorKey, err.Error())
+	}
 
 	_ = l.handler.Handle(ctx, r)
 }
diff --git a/logger_test.go b/logger_test.go
index 55a0d95..27b35d6 100644
--- a/logger_test.go
+++ b/logger_test.go
@@ -52,6 +52,7 @@ func TestLoggerLogWithConfigOverride(t *testing.T) {
 		slog.Any(nameKey, "test"),
 		slog.Any("arg1", "val1"),
 		slog.Any(stackKey, fmt.Sprintf("%+v", err)),
+		slog.Any(errorKey, err.Error()),
 	}
 	assertRecordAttrs(t, handler.records[0], attrs...)
 }