diff --git a/database/migrations/2026_08_17_000000_add_task_pagination_indexes.php b/database/migrations/2026_08_17_000000_add_task_pagination_indexes.php
new file mode 100644
index 0000000000..8a5042068e
--- /dev/null
+++ b/database/migrations/2026_08_17_000000_add_task_pagination_indexes.php
@@ -0,0 +1,78 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration {
+    private const TABLE = 'process_request_tokens';
+
+    private const COUNT_INDEX = 'process_request_tokens_prt_completed_task_count';
+
+    private const PAGE_INDEX = 'process_request_tokens_prt_task_created';
+
+    /**
+     * Add indexes used by completed-task pagination.
+     *
+     * Run this migration during a low-traffic window. Although MySQL builds the
+     * indexes online, it can briefly wait for metadata locks on a large table.
+     */
+    public function up(): void
+    {
+        $clauses = [];
+
+        if (!Schema::hasIndex(self::TABLE, self::COUNT_INDEX)) {
+            $clauses[] = sprintf(
+                'ADD INDEX `%s` (`status`, `is_self_service`, `element_type`, `element_name`)',
+                self::COUNT_INDEX
+            );
+        }
+
+        if (!Schema::hasIndex(self::TABLE, self::PAGE_INDEX)) {
+            $clauses[] = sprintf(
+                'ADD INDEX `%s` (`is_self_service`, `created_at` DESC, `status`, `element_type`, `element_name`)',
+                self::PAGE_INDEX
+            );
+        }
+
+        $this->alterTable($clauses);
+        $this->refreshStatistics();
+    }
+
+    /**
+     * Remove completed-task pagination indexes.
+     */
+    public function down(): void
+    {
+        $clauses = [];
+
+        if (Schema::hasIndex(self::TABLE, self::COUNT_INDEX)) {
+            $clauses[] = sprintf('DROP INDEX `%s`', self::COUNT_INDEX);
+        }
+
+        if (Schema::hasIndex(self::TABLE, self::PAGE_INDEX)) {
+            $clauses[] = sprintf('DROP INDEX `%s`', self::PAGE_INDEX);
+        }
+
+        $this->alterTable($clauses);
+        $this->refreshStatistics();
+    }
+
+    private function alterTable(array $clauses): void
+    {
+        if ($clauses === []) {
+            return;
+        }
+
+        DB::statement(sprintf(
+            'ALTER TABLE `%s` %s, ALGORITHM=INPLACE, LOCK=NONE',
+            self::TABLE,
+            implode(', ', $clauses)
+        ));
+    }
+
+    private function refreshStatistics(): void
+    {
+        DB::statement(sprintf('ANALYZE TABLE `%s`', self::TABLE));
+    }
+};
diff --git a/tests/Feature/Migrations/AddTaskPaginationIndexesTest.php b/tests/Feature/Migrations/AddTaskPaginationIndexesTest.php
new file mode 100644
index 0000000000..b67d9ea811
--- /dev/null
+++ b/tests/Feature/Migrations/AddTaskPaginationIndexesTest.php
@@ -0,0 +1,89 @@
+<?php
+
+namespace Tests\Feature\Migrations;
+
+use Illuminate\Database\Events\QueryExecuted;
+use Illuminate\Support\Facades\DB;
+use Illuminate\Support\Facades\Schema;
+use Tests\TestCase;
+
+class AddTaskPaginationIndexesTest extends TestCase
+{
+    private const MIGRATION_PATH = 'database/migrations/2026_08_17_000000_add_task_pagination_indexes.php';
+
+    private const COUNT_INDEX = 'process_request_tokens_prt_completed_task_count';
+
+    private const PAGE_INDEX = 'process_request_tokens_prt_task_created';
+
+    protected $connectionsToTransact = [];
+
+    public function testUpCreatesBothIndexesAndRefreshesStatistics(): void
+    {
+        $migration = $this->migration();
+        $migration->down();
+
+        try {
+            $queries = $this->captureQueries(fn () => $migration->up());
+
+            $this->assertTrue(Schema::hasIndex('process_request_tokens', self::COUNT_INDEX));
+            $this->assertTrue(Schema::hasIndex('process_request_tokens', self::PAGE_INDEX));
+            $this->assertStatisticsWereRefreshed($queries);
+        } finally {
+            $migration->up();
+        }
+    }
+
+    public function testUpIsIdempotentAndStillRefreshesStatistics(): void
+    {
+        $migration = $this->migration();
+        $migration->up();
+
+        $queries = $this->captureQueries(fn () => $migration->up());
+
+        $this->assertTrue(Schema::hasIndex('process_request_tokens', self::COUNT_INDEX));
+        $this->assertTrue(Schema::hasIndex('process_request_tokens', self::PAGE_INDEX));
+        $this->assertStatisticsWereRefreshed($queries);
+        $this->assertFalse(collect($queries)->contains(
+            fn (string $query) => str_starts_with($query, 'ALTER TABLE `process_request_tokens`')
+        ));
+    }
+
+    public function testDownRemovesBothIndexesAndRefreshesStatistics(): void
+    {
+        $migration = $this->migration();
+        $migration->up();
+
+        try {
+            $queries = $this->captureQueries(fn () => $migration->down());
+
+            $this->assertFalse(Schema::hasIndex('process_request_tokens', self::COUNT_INDEX));
+            $this->assertFalse(Schema::hasIndex('process_request_tokens', self::PAGE_INDEX));
+            $this->assertStatisticsWereRefreshed($queries);
+        } finally {
+            $migration->up();
+        }
+    }
+
+    private function migration()
+    {
+        return include base_path(self::MIGRATION_PATH);
+    }
+
+    private function captureQueries(callable $callback): array
+    {
+        $queries = [];
+
+        DB::listen(function (QueryExecuted $query) use (&$queries) {
+            $queries[] = $query->sql;
+        });
+
+        $callback();
+
+        return $queries;
+    }
+
+    private function assertStatisticsWereRefreshed(array $queries): void
+    {
+        $this->assertContains('ANALYZE TABLE `process_request_tokens`', $queries);
+    }
+}