diff --git a/clients/bigquery/storagewrite.go b/clients/bigquery/storagewrite.go
index aa93dd6c4..44a72e3f3 100644
--- a/clients/bigquery/storagewrite.go
+++ b/clients/bigquery/storagewrite.go
@@ -129,7 +129,7 @@ func encodePacked64DatetimeSeconds(dateTime time.Time) int64 {
 
 // This is a reimplementation of https://github.com/googleapis/java-bigquerystorage/blob/f79acb5cfdd12253bca1c41551c478400120d2f9/google-cloud-bigquerystorage/src/main/java/com/google/cloud/bigquery/storage/v1/CivilTimeEncoder.java#L248
 func encodePacked64DatetimeMicros(dateTime time.Time) int64 {
-	return encodePacked64DatetimeSeconds(dateTime)<<microLength | int64(dateTime.Nanosecond()/1_000)
+	return encodePacked64DatetimeSeconds(dateTime)<<microLength | int64(dateTime.Nanosecond()/1000)
 }
 
 func rowToMessage(row map[string]any, columns []columns.Column, messageDescriptor protoreflect.MessageDescriptor) (*dynamicpb.Message, error) {
diff --git a/clients/bigquery/storagewrite_test.go b/clients/bigquery/storagewrite_test.go
index 98511d10b..3d5f45b80 100644
--- a/clients/bigquery/storagewrite_test.go
+++ b/clients/bigquery/storagewrite_test.go
@@ -112,45 +112,45 @@ func TestEncodePacked32TimeSeconds(t *testing.T) {
 }
 
 func TestEncodePacked64DatetimeSeconds(t *testing.T) {
-	_ts := time.Date(2024, 10, 24, 13, 1, 2, 3000000, time.UTC)
-	_expected := 2024<<26 + 10<<22 + 24<<17 + int64(encodePacked32TimeSeconds(_ts))
+	ts := time.Date(2024, 10, 24, 13, 1, 2, 3000000, time.UTC)
+	expected := 2024<<26 + 10<<22 + 24<<17 + int64(encodePacked32TimeSeconds(ts))
 
 	// Time
-	assert.Equal(t, _expected, encodePacked64DatetimeSeconds(_ts))
-	assert.Equal(t, _expected+1<<0, encodePacked64DatetimeSeconds(_ts.Add(time.Duration(1)*time.Second)))
-	assert.Equal(t, _expected+1<<6, encodePacked64DatetimeSeconds(_ts.Add(time.Duration(1)*time.Minute)))
-	assert.Equal(t, _expected+1<<12, encodePacked64DatetimeSeconds(_ts.Add(time.Duration(1)*time.Hour)))
-	assert.Equal(t, _expected+1<<12+1<<0, encodePacked64DatetimeSeconds(_ts.Add(time.Duration(1)*time.Hour+time.Duration(1)*time.Second)))
+	assert.Equal(t, expected, encodePacked64DatetimeSeconds(ts))
+	assert.Equal(t, expected+1<<0, encodePacked64DatetimeSeconds(ts.Add(time.Duration(1)*time.Second)))
+	assert.Equal(t, expected+1<<6, encodePacked64DatetimeSeconds(ts.Add(time.Duration(1)*time.Minute)))
+	assert.Equal(t, expected+1<<12, encodePacked64DatetimeSeconds(ts.Add(time.Duration(1)*time.Hour)))
+	assert.Equal(t, expected+1<<12+1<<0, encodePacked64DatetimeSeconds(ts.Add(time.Duration(1)*time.Hour+time.Duration(1)*time.Second)))
 
 	// Day
-	assert.Equal(t, _expected+1<<17, encodePacked64DatetimeSeconds(_ts.Add(time.Duration(24)*time.Hour)))
+	assert.Equal(t, expected+1<<17, encodePacked64DatetimeSeconds(ts.Add(time.Duration(24)*time.Hour)))
 	// Month
-	assert.Equal(t, _expected+1<<22, encodePacked64DatetimeSeconds(_ts.AddDate(0, 1, 0)))
+	assert.Equal(t, expected+1<<22, encodePacked64DatetimeSeconds(ts.AddDate(0, 1, 0)))
 	// Year
-	assert.Equal(t, _expected+1<<26, encodePacked64DatetimeSeconds(_ts.AddDate(1, 0, 0)))
+	assert.Equal(t, expected+1<<26, encodePacked64DatetimeSeconds(ts.AddDate(1, 0, 0)))
 	// Month and year
-	assert.Equal(t, _expected+1<<22+1<<26, encodePacked64DatetimeSeconds(_ts.AddDate(1, 1, 0)))
+	assert.Equal(t, expected+1<<22+1<<26, encodePacked64DatetimeSeconds(ts.AddDate(1, 1, 0)))
 }
 
 func TestEncodePacked64DatetimeMicros(t *testing.T) {
-	_ts := time.Date(2024, 10, 24, 13, 1, 2, 123456789, time.UTC)
-	_expected := encodePacked64DatetimeSeconds(_ts)<<20 | int64(_ts.Nanosecond()/1000)
+	ts := time.Date(2024, 10, 24, 13, 1, 2, 123456789, time.UTC)
+	expected := encodePacked64DatetimeSeconds(ts)<<20 | int64(ts.Nanosecond()/1000)
 
 	// Time
-	assert.Equal(t, _expected, encodePacked64DatetimeMicros(_ts))
-	assert.Equal(t, _expected+1<<(0+20), encodePacked64DatetimeMicros(_ts.Add(time.Duration(1)*time.Second)))
-	assert.Equal(t, _expected+1<<(6+20), encodePacked64DatetimeMicros(_ts.Add(time.Duration(1)*time.Minute)))
-	assert.Equal(t, _expected+1<<(12+20), encodePacked64DatetimeMicros(_ts.Add(time.Duration(1)*time.Hour)))
-	assert.Equal(t, _expected+1<<(12+20)+1<<(0+20), encodePacked64DatetimeMicros(_ts.Add(time.Duration(1)*time.Hour+time.Duration(1)*time.Second)))
+	assert.Equal(t, expected, encodePacked64DatetimeMicros(ts))
+	assert.Equal(t, expected+1<<(0+20), encodePacked64DatetimeMicros(ts.Add(time.Duration(1)*time.Second)))
+	assert.Equal(t, expected+1<<(6+20), encodePacked64DatetimeMicros(ts.Add(time.Duration(1)*time.Minute)))
+	assert.Equal(t, expected+1<<(12+20), encodePacked64DatetimeMicros(ts.Add(time.Duration(1)*time.Hour)))
+	assert.Equal(t, expected+1<<(12+20)+1<<(0+20), encodePacked64DatetimeMicros(ts.Add(time.Duration(1)*time.Hour+time.Duration(1)*time.Second)))
 
 	// Day
-	assert.Equal(t, _expected+1<<(17+20), encodePacked64DatetimeMicros(_ts.Add(time.Duration(24)*time.Hour)))
+	assert.Equal(t, expected+1<<(17+20), encodePacked64DatetimeMicros(ts.Add(time.Duration(24)*time.Hour)))
 	// Month
-	assert.Equal(t, _expected+1<<(22+20), encodePacked64DatetimeMicros(_ts.AddDate(0, 1, 0)))
+	assert.Equal(t, expected+1<<(22+20), encodePacked64DatetimeMicros(ts.AddDate(0, 1, 0)))
 	// Year
-	assert.Equal(t, _expected+1<<(26+20), encodePacked64DatetimeMicros(_ts.AddDate(1, 0, 0)))
+	assert.Equal(t, expected+1<<(26+20), encodePacked64DatetimeMicros(ts.AddDate(1, 0, 0)))
 	// Month and year
-	assert.Equal(t, _expected+1<<(26+20)+1<<(22+20), encodePacked64DatetimeMicros(_ts.AddDate(1, 1, 0)))
+	assert.Equal(t, expected+1<<(26+20)+1<<(22+20), encodePacked64DatetimeMicros(ts.AddDate(1, 1, 0)))
 }
 
 func TestRowToMessage(t *testing.T) {