diff --git a/src/ast.rs b/src/ast.rs
index d4ca7d2f75..b453e1b681 100644
--- a/src/ast.rs
+++ b/src/ast.rs
@@ -160,6 +160,10 @@ impl TypeNature {
     pub fn is_real(&self) -> bool {
         self.derives(TypeNature::Real)
     }
+
+    pub fn is_bit(&self) -> bool {
+        self.derives(TypeNature::Bit)
+    }
 }
 
 impl DirectAccessType {
diff --git a/src/resolver.rs b/src/resolver.rs
index 611f698adb..2636f12ae8 100644
--- a/src/resolver.rs
+++ b/src/resolver.rs
@@ -898,10 +898,14 @@ impl<'i> TypeAnnotator<'i> {
                         let bigger_type = if l_intrinsic_type.is_bool() && r_intrinsic_type.is_bool() {
                             left_type
                         } else {
-                            let dint = self.index.get_type_or_panic(DINT_TYPE);
+                            let ty = if left_type.is_bit() && right_type.is_bit() {
+                                right_type
+                            } else {
+                                self.index.get_type_or_panic(DINT_TYPE)
+                            };
                             get_bigger_type(
                                 get_bigger_type(left_type, right_type, self.index),
-                                dint,
+                                ty,
                                 self.index,
                             )
                         };
diff --git a/src/resolver/tests/resolve_expressions_tests.rs b/src/resolver/tests/resolve_expressions_tests.rs
index e722318cc3..acee32b85d 100644
--- a/src/resolver/tests/resolve_expressions_tests.rs
+++ b/src/resolver/tests/resolve_expressions_tests.rs
@@ -557,7 +557,7 @@ fn resolve_binary_expressions() {
     let statements = &unit.implementations[0].statements;
 
     let expected_types = vec![
-        "DINT", "DINT", "DINT", "LWORD", "DINT", "DINT", "DINT", "DINT", "DINT", "DINT", "LINT", "ULINT",
+        "BYTE", "WORD", "DWORD", "LWORD", "DINT", "DINT", "DINT", "DINT", "DINT", "DINT", "LINT", "ULINT",
     ];
     let type_names: Vec<&str> =
         statements.iter().map(|s| annotations.get_type_or_void(s, &index).get_name()).collect();
@@ -805,7 +805,7 @@ fn qualified_expressions_resolve_types() {
     let (annotations, _) = TypeAnnotator::visit_unit(&index, &unit, id_provider);
     let statements = &unit.implementations[1].statements;
 
-    let expected_types = vec!["BYTE", "WORD", "DWORD", "LWORD", "DINT", "DINT", "LWORD"];
+    let expected_types = vec!["BYTE", "WORD", "DWORD", "LWORD", "WORD", "DWORD", "LWORD"];
     let type_names: Vec<&str> =
         statements.iter().map(|s| annotations.get_type_or_void(s, &index).get_name()).collect();
 
diff --git a/src/typesystem.rs b/src/typesystem.rs
index c62c3439bc..d2258ca41b 100644
--- a/src/typesystem.rs
+++ b/src/typesystem.rs
@@ -138,6 +138,10 @@ impl DataType {
         self.nature.is_real()
     }
 
+    pub fn is_bit(&self) -> bool {
+        self.nature.is_bit()
+    }
+
     /// returns true if this type is an internal, auto-generated type
     pub fn is_internal(&self) -> bool {
         self.location.is_internal()
diff --git a/src/validation/tests/generic_validation_tests.rs b/src/validation/tests/generic_validation_tests.rs
index 506085dcb2..a13fa81023 100644
--- a/src/validation/tests/generic_validation_tests.rs
+++ b/src/validation/tests/generic_validation_tests.rs
@@ -1118,6 +1118,20 @@ fn any_bit_allows_bits() {
 		FUNCTION func3  : INT VAR x : WORD; END_VAR test(x); END_FUNCTION
 		FUNCTION func4  : INT VAR x : DWORD; END_VAR test(x); END_FUNCTION
 		FUNCTION func5  : INT VAR x : LWORD; END_VAR test(x); END_FUNCTION
+        // binary expressions
+        FUNCTION func6  : INT 
+        VAR
+        a : BOOL;
+        b : BYTE;
+        c : WORD;
+        d : DWORD;
+        e : LWORD;
+        END_VAR
+            test(a + b);
+            test(d - c);
+            test(d * d);
+            test(b + e);
+        END_FUNCTION
     ";
 
     let diagnostics = parse_and_validate(src);