diff --git a/dialects/postgresql/builder_test.go b/dialects/postgresql/builder_test.go
index 61b4ce0..be598a1 100644
--- a/dialects/postgresql/builder_test.go
+++ b/dialects/postgresql/builder_test.go
@@ -77,6 +77,11 @@ func TestAlterTableAddColumn(t *testing.T) {
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, createdAtColumn)
 	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
 
+	activatedAtColumn := testutils.FakeActivatedAtColumn(t)
+	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"activated_at\" TIMESTAMP(6) NOT NULL DEFAULT '1900-01-01 00:00:00.000000';"
+	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, activatedAtColumn)
+	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
+
 	priceColumn := testutils.FakePriceColumn(t)
 	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"price\" NUMERIC(17,2) NOT NULL DEFAULT 0.0;"
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, priceColumn)
diff --git a/dialects/sqlite/builder_test.go b/dialects/sqlite/builder_test.go
index 222e1fa..5ffcdb1 100644
--- a/dialects/sqlite/builder_test.go
+++ b/dialects/sqlite/builder_test.go
@@ -57,6 +57,11 @@ func TestAlterTableAddColumn(t *testing.T) {
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, createdAtColumn)
 	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
 
+	activatedAtColumn := testutils.FakeActivatedAtColumn(t)
+	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"activated_at\" DATETIME NOT NULL DEFAULT '1900-01-01 00:00:00.000000';"
+	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, activatedAtColumn)
+	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
+
 	priceColumn := testutils.FakePriceColumn(t)
 	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"price\" REAL NOT NULL DEFAULT 0.0;"
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, priceColumn)
diff --git a/dialects/sqlserver/builder_test.go b/dialects/sqlserver/builder_test.go
index e9af989..4ceb78a 100644
--- a/dialects/sqlserver/builder_test.go
+++ b/dialects/sqlserver/builder_test.go
@@ -57,6 +57,11 @@ func TestAlterTableAddColumn(t *testing.T) {
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, createdAtColumn)
 	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
 
+	activatedAtColumn := testutils.FakeActivatedAtColumn(t)
+	expectedSQL = "ALTER TABLE [user] ADD COLUMN [activated_at] DATETIME2(6) NOT NULL DEFAULT '1900-01-01 00:00:00.000000';"
+	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, activatedAtColumn)
+	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
+
 	priceColumn := testutils.FakePriceColumn(t)
 	expectedSQL = "ALTER TABLE [user] ADD COLUMN [price] MONEY NOT NULL DEFAULT 0.0;"
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, priceColumn)
diff --git a/internal/builder_generic.go b/internal/builder_generic.go
index b2ae8a8..b9ba9fb 100644
--- a/internal/builder_generic.go
+++ b/internal/builder_generic.go
@@ -70,10 +70,12 @@ func (sb *genericSQLBuilder) AlterTableAddColumn(table string, column schema.Col
 		switch column.Type() {
 		case schema.Boolean, schema.Integer:
 			defaultValue += "0"
-		case schema.DateTime, schema.DateTimeOffSet:
-			defaultValue += "'1900-01-01 00:00:00.000000 +00:00'"
+		case schema.DateTime:
+			defaultValue += "'1900-01-01 00:00:00.000000'"
 		case schema.Monetary, schema.Decimal:
 			defaultValue += "0.0"
+		case schema.DateTimeOffSet:
+			defaultValue += "'1900-01-01 00:00:00.000000 +00:00'"
 		default:
 			defaultValue += "''"
 		}
diff --git a/internal/builder_generic_test.go b/internal/builder_generic_test.go
index 0fe57cd..5e69b59 100644
--- a/internal/builder_generic_test.go
+++ b/internal/builder_generic_test.go
@@ -50,6 +50,11 @@ func TestAlterTableAddColumn(t *testing.T) {
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, createdAtColumn)
 	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
 
+	activatedAtColumn := testutils.FakeActivatedAtColumn(t)
+	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"activated_at\" <<TYPE_3>> DEFAULT '1900-01-01 00:00:00.000000';"
+	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, activatedAtColumn)
+	testutils.AssertEqualWithLabel(t, expectedSQL, returnedSQL, "SQLBuilder.AlterTableAddColumn")
+
 	priceColumn := testutils.FakePriceColumn(t)
 	expectedSQL = "ALTER TABLE \"user\" ADD COLUMN \"price\" <<TYPE_2>> DEFAULT 0.0;"
 	returnedSQL = sqlBuilder.AlterTableAddColumn(userTableName, priceColumn)
diff --git a/internal/testutils/fake.go b/internal/testutils/fake.go
index 25691dc..0837e02 100644
--- a/internal/testutils/fake.go
+++ b/internal/testutils/fake.go
@@ -167,6 +167,16 @@ func FakeCreatedAtColumn(t *testing.T) schema.Column {
 	})
 }
 
+func FakeActivatedAtColumn(t *testing.T) schema.Column {
+	return schema.NewColumn(schema.NewColumnParams{
+		Name:          "activated_at",
+		Type:          schema.DateTime,
+		PrimaryKey:    false,
+		NotNull:       true,
+		AutoIncrement: false,
+	})
+}
+
 func FakeScoreColumn(t *testing.T) schema.Column {
 	return schema.NewColumn(schema.NewColumnParams{
 		Name:          "score",