diff --git a/pkg/util/size.go b/pkg/util/size.go
index dfc88c614..33b7b60fc 100644
--- a/pkg/util/size.go
+++ b/pkg/util/size.go
@@ -43,7 +43,7 @@ func GetVarStringSize(value string) int {
 
 // GetVarSize return the size om bytes of a variable. This implementation is not exactly like the C#
 // (reference: GetVarSize<T>(this T[] value), https://github.com/neo-project/neo/blob/master/neo/IO/Helper.cs#L53) as in the C# variable
-// like Uint160, Uint256 are not supported. @TODO: make sure to have full unit tests coverage.
+// like Uint160, Uint256 are not supported.
 func GetVarSize(value interface{}) int {
 	v := reflect.ValueOf(value)
 	switch v.Kind() {
diff --git a/pkg/util/size_test.go b/pkg/util/size_test.go
index f4c57b475..15eb77523 100644
--- a/pkg/util/size_test.go
+++ b/pkg/util/size_test.go
@@ -2,11 +2,28 @@ package util
 
 import (
 	"fmt"
+	"io"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
 )
 
+// Mock structure to test getting size of an array of serializable things
+type smthSerializable struct {
+}
+
+func (*smthSerializable) DecodeBinary(io.Reader) error {
+	return nil
+}
+
+func (*smthSerializable) EncodeBinary(io.Writer) error {
+	return nil
+}
+
+func (*smthSerializable) Size() int {
+	return 42
+}
+
 func TestVarSize(t *testing.T) {
 	testCases := []struct {
 		variable interface{}
@@ -38,6 +55,31 @@ func TestVarSize(t *testing.T) {
 			"test_int_5",
 			5,
 		},
+		{
+			uint(252),
+			"test_uint_1",
+			1,
+		},
+		{
+			uint(253),
+			"test_uint_2",
+			3,
+		},
+		{
+			uint(65535),
+			"test_uint_3",
+			3,
+		},
+		{
+			uint(65536),
+			"test_uint_4",
+			5,
+		},
+		{
+			uint(4294967295),
+			"test_uint_5",
+			5,
+		},
 		{
 			[]byte{1, 2, 4, 5, 6},
 			"test_[]byte_1",
@@ -128,6 +170,10 @@ func TestVarSize(t *testing.T) {
 			"test_string_3",
 			41,
 		},
+		{[]*smthSerializable{&smthSerializable{}, &smthSerializable{}},
+			"test_Serializable",
+			2 * 42 + 1,
+		},
 	}
 
 	for _, tc := range testCases {
@@ -137,3 +183,12 @@ func TestVarSize(t *testing.T) {
 		})
 	}
 }
+
+func TestVarSizePanic(t *testing.T) {
+	defer func() {
+		r := recover()
+		assert.NotNil(t, r)
+	}()
+
+	_ = GetVarSize(t)
+}