diff --git a/proto/date.go b/proto/date.go
index 39d3e0d0..3f850327 100644
--- a/proto/date.go
+++ b/proto/date.go
@@ -31,9 +31,10 @@ func (d Date) String() string {
 	return d.Time().UTC().Format(DateLayout)
 }
 
-// ToDate returns Date of time.Time in UTC.
+// ToDate returns Date of time.Time.
 func ToDate(t time.Time) Date {
-	return Date(t.Unix() / secInDay)
+	_, offset := t.Zone()
+	return Date((t.Unix() + int64(offset)) / secInDay)
 }
 
 // NewDate returns the Date corresponding to year, month and day in UTC.
diff --git a/proto/date32.go b/proto/date32.go
index f4b25138..00ec39ce 100644
--- a/proto/date32.go
+++ b/proto/date32.go
@@ -26,9 +26,10 @@ func (d Date32) String() string {
 	return d.Time().Format(DateLayout)
 }
 
-// ToDate32 returns Date32 of time.Time in UTC.
+// ToDate32 returns Date32 of time.Time.
 func ToDate32(t time.Time) Date32 {
-	return Date32((t.Unix() - date32Epoch) / secInDay)
+	_, offset := t.Zone()
+	return Date32((t.Unix() + int64(offset) - date32Epoch) / secInDay)
 }
 
 // NewDate32 returns the Date32 corresponding to year, month and day in UTC.
diff --git a/proto/date32_test.go b/proto/date32_test.go
index 27630c4a..d7a37ca2 100644
--- a/proto/date32_test.go
+++ b/proto/date32_test.go
@@ -35,6 +35,27 @@ func TestDate32_Time(t *testing.T) {
 	})
 }
 
+func TestToDate32(t *testing.T) {
+	for _, tc := range []struct {
+		Value string
+	}{
+		{Value: "2006-01-02T06:04:03+07:00"},
+		{Value: "2008-01-02T06:44:15+03:00"},
+		{Value: "2009-01-01T06:03:31+12:00"},
+		{Value: "2006-12-31T22:04:41-06:30"},
+	} {
+		t.Run(tc.Value, func(t *testing.T) {
+			v, err := time.Parse(time.RFC3339, tc.Value)
+			require.NoError(t, err)
+			d := ToDate32(v)
+			expected := NewDate32(v.Year(), v.Month(), v.Day())
+			assert.Equal(t, v.Format(DateLayout), d.String())
+			assert.Equal(t, expected.String(), d.String())
+			assert.Equal(t, expected, d)
+		})
+	}
+}
+
 func BenchmarkDate32_Time(b *testing.B) {
 	b.ReportAllocs()
 
diff --git a/proto/date_test.go b/proto/date_test.go
index a92ce2d3..965c38f3 100644
--- a/proto/date_test.go
+++ b/proto/date_test.go
@@ -5,6 +5,7 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestDate_Time(t *testing.T) {
@@ -34,6 +35,27 @@ func TestDate_Time(t *testing.T) {
 	})
 }
 
+func TestToDate(t *testing.T) {
+	for _, tc := range []struct {
+		Value string
+	}{
+		{Value: "2006-01-02T06:04:03+07:00"},
+		{Value: "2008-01-02T06:44:15+03:00"},
+		{Value: "2009-01-01T06:03:31+12:00"},
+		{Value: "2006-12-31T22:04:41-06:30"},
+	} {
+		t.Run(tc.Value, func(t *testing.T) {
+			v, err := time.Parse(time.RFC3339, tc.Value)
+			require.NoError(t, err)
+			d := ToDate(v)
+			expected := NewDate(v.Year(), v.Month(), v.Day())
+			assert.Equal(t, v.Format(DateLayout), d.String())
+			assert.Equal(t, expected.String(), d.String())
+			assert.Equal(t, expected, d)
+		})
+	}
+}
+
 func BenchmarkDate_Time(b *testing.B) {
 	b.ReportAllocs()