diff --git a/src/bundle/Core/Resources/config/doctrine_migrations.yml b/src/bundle/Core/Resources/config/doctrine_migrations.yml
index 3ef2ca6eb5..62bf1c9cb4 100644
--- a/src/bundle/Core/Resources/config/doctrine_migrations.yml
+++ b/src/bundle/Core/Resources/config/doctrine_migrations.yml
@@ -78,3 +78,11 @@ services:
             $connection: '@ibexa.persistence.connection'
         tags:
             - { name: !php/const Ibexa\Contracts\DoctrineMigrations\Migrations\IbexaMigrationTag::TAG }
+
+    Ibexa\Bundle\RepositoryInstaller\Migration\ConvertPostgreSqlSerialColumnsToIdentityMigration:
+        autowire: true
+        public: false
+        arguments:
+            $connection: '@ibexa.persistence.connection'
+        tags:
+            - { name: !php/const Ibexa\Contracts\DoctrineMigrations\Migrations\IbexaMigrationTag::TAG }
diff --git a/src/bundle/RepositoryInstaller/Migration/ConvertPostgreSqlSerialColumnsToIdentityMigration.php b/src/bundle/RepositoryInstaller/Migration/ConvertPostgreSqlSerialColumnsToIdentityMigration.php
new file mode 100644
index 0000000000..a78b22f86c
--- /dev/null
+++ b/src/bundle/RepositoryInstaller/Migration/ConvertPostgreSqlSerialColumnsToIdentityMigration.php
@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * @copyright Copyright (C) Ibexa AS. All rights reserved.
+ * @license For full copyright and license information view LICENSE file distributed with this source code.
+ */
+declare(strict_types=1);
+
+namespace Ibexa\Bundle\RepositoryInstaller\Migration;
+
+use DateTimeImmutable;
+use Doctrine\DBAL\Schema\Schema;
+use Ibexa\Contracts\DoctrineMigrations\Migrations\AbstractSqlMigration;
+use Ibexa\Contracts\DoctrineMigrations\Migrations\IbexaMigrationInterface;
+use Ibexa\Contracts\DoctrineMigrations\Migrations\SqlPlatform;
+
+/**
+ * Turns the SERIAL columns of the core tables into identity columns on PostgreSQL, as a fresh 6.0
+ * install creates them.
+ *
+ * Doctrine DBAL 4 creates an autoincrement column on PostgreSQL as GENERATED BY DEFAULT AS
+ * IDENTITY, where DBAL 2 and 3 used SERIAL: a column defaulting to the next value of its own
+ * sequence. The install migrations, which a 6.0 install runs too, are the ones from 4.6 and 5.0, so
+ * they created these as SERIAL, and a database upgraded from 5.0 keeps them.
+ * sql/convert-serial-columns-to-identity-postgresql.sql turns each SERIAL column into an identity
+ * column that carries on from its sequence's current value, drops the old sequence, and skips a
+ * column that's no longer SERIAL.
+ *
+ * This is kept apart from the other 6.0 migrations on purpose: SERIAL columns work the same for
+ * inserts, so leaving this one out keeps them as they are.
+ */
+final class ConvertPostgreSqlSerialColumnsToIdentityMigration extends AbstractSqlMigration implements IbexaMigrationInterface
+{
+    public function getDescription(): string
+    {
+        return 'Turns the core SERIAL columns into identity columns on PostgreSQL';
+    }
+
+    public static function getTargetVersion(): string
+    {
+        return '6.0.0';
+    }
+
+    public static function getCreationDate(): DateTimeImmutable
+    {
+        return new DateTimeImmutable('2026-10-06 00:00:03');
+    }
+
+    public function up(Schema $schema): void
+    {
+        $this->abortIfUnsupportedPlatform(SqlPlatform::MYSQL, SqlPlatform::MARIADB, SqlPlatform::POSTGRESQL, SqlPlatform::SQLITE);
+
+        if ($this->isPostgreSQL()) {
+            $this->addSqlFile(__DIR__ . '/sql/convert-serial-columns-to-identity-postgresql.sql');
+        }
+    }
+}
diff --git a/src/bundle/RepositoryInstaller/Migration/sql/convert-serial-columns-to-identity-postgresql.sql b/src/bundle/RepositoryInstaller/Migration/sql/convert-serial-columns-to-identity-postgresql.sql
new file mode 100644
index 0000000000..f417fee97e
--- /dev/null
+++ b/src/bundle/RepositoryInstaller/Migration/sql/convert-serial-columns-to-identity-postgresql.sql
@@ -0,0 +1,60 @@
+DO $$
+DECLARE
+    serial_column record;
+    sequence_name text;
+    old_last_value bigint;
+    old_is_called boolean;
+BEGIN
+    FOR serial_column IN SELECT * FROM (VALUES
+        ('ibexa_content', 'id'),
+        ('ibexa_content_bookmark', 'id'),
+        ('ibexa_content_field', 'id'),
+        ('ibexa_content_relation', 'id'),
+        ('ibexa_content_tree', 'node_id'),
+        ('ibexa_content_type', 'id'),
+        ('ibexa_content_type_field_definition', 'id'),
+        ('ibexa_content_type_group', 'id'),
+        ('ibexa_content_version', 'id'),
+        ('ibexa_image_file', 'id'),
+        ('ibexa_keyword', 'id'),
+        ('ibexa_keyword_field_link', 'id'),
+        ('ibexa_node_assignment', 'id'),
+        ('ibexa_notification', 'id'),
+        ('ibexa_object_state', 'id'),
+        ('ibexa_object_state_group', 'id'),
+        ('ibexa_package', 'id'),
+        ('ibexa_policy', 'id'),
+        ('ibexa_policy_limitation', 'id'),
+        ('ibexa_policy_limitation_value', 'id'),
+        ('ibexa_role', 'id'),
+        ('ibexa_search_object_word_link', 'id'),
+        ('ibexa_search_word', 'id'),
+        ('ibexa_section', 'id'),
+        ('ibexa_setting', 'id'),
+        ('ibexa_token', 'id'),
+        ('ibexa_token_type', 'id'),
+        ('ibexa_url', 'id'),
+        ('ibexa_url_alias', 'id'),
+        ('ibexa_url_alias_ml_incr', 'id'),
+        ('ibexa_url_wildcard', 'id'),
+        ('ibexa_user_accountkey', 'id'),
+        ('ibexa_user_preference', 'id'),
+        ('ibexa_user_role', 'id')
+    ) AS c (table_name, column_name)
+    LOOP
+        -- A SERIAL column defaults to nextval('<sequence>'::regclass); an identity column has no default.
+        SELECT substring(column_default FROM 'nextval\(''([^'']+)''::regclass\)') INTO sequence_name
+        FROM information_schema.columns
+        WHERE table_schema = current_schema()
+            AND table_name = serial_column.table_name
+            AND column_name = serial_column.column_name;
+        CONTINUE WHEN sequence_name IS NULL;
+
+        EXECUTE format('SELECT last_value, is_called FROM %s', sequence_name) INTO old_last_value, old_is_called;
+        EXECUTE format('ALTER TABLE %I ALTER %I DROP DEFAULT', serial_column.table_name, serial_column.column_name);
+        EXECUTE format('DROP SEQUENCE %s', sequence_name);
+        EXECUTE format('ALTER TABLE %I ALTER %I ADD GENERATED BY DEFAULT AS IDENTITY', serial_column.table_name, serial_column.column_name);
+        PERFORM setval(pg_get_serial_sequence(serial_column.table_name, serial_column.column_name), old_last_value, old_is_called);
+    END LOOP;
+END
+$$;