diff --git a/openapi.yaml b/openapi.yaml
index 9db79e35..1a02883a 100644
--- a/openapi.yaml
+++ b/openapi.yaml
@@ -8843,6 +8843,47 @@ paths:
         '403':
           $ref: '#/components/responses/Forbidden'
 
+  /modules/self-serve/lane/wash/my-active-wash:
+    get:
+      tags:
+        - Modules
+      summary: Get the authenticated customer's active self-serve wash
+      description: |
+        Returns the latest active self-serve wash for the authenticated customer,
+        without requiring the frontend to know or poll a lane id.
+      operationId: getMyActiveSelfServeWash
+      responses:
+        '200':
+          description: Active self-serve wash details resolved
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  lane_id:
+                    type: integer
+                  status:
+                    type: string
+                  in_progress:
+                    type: boolean
+                  elapsed_minutes:
+                    type: integer
+                  session:
+                    type: object
+                    nullable: true
+                  customer:
+                    type: object
+                    nullable: true
+                  vehicle:
+                    type: object
+                    nullable: true
+        '401':
+          $ref: '#/components/responses/Unauthorized'
+        '403':
+          $ref: '#/components/responses/Forbidden'
+        '404':
+          $ref: '#/components/responses/NotFound'
+
   /modules/self-serve/sessions:
     get:
       tags:
@@ -18688,4 +18729,3 @@ components:
         data:
           $ref: '#/components/schemas/DepartmentDailyReportOutsideHoursTrendPayload'
 
-
diff --git a/services/nginx/app/openapi.yaml b/services/nginx/app/openapi.yaml
index cc892f50..2b9d91d3 100644
--- a/services/nginx/app/openapi.yaml
+++ b/services/nginx/app/openapi.yaml
@@ -9208,6 +9208,47 @@ paths:
         '403':
           $ref: '#/components/responses/Forbidden'
 
+  /modules/self-serve/lane/wash/my-active-wash:
+    get:
+      tags:
+        - Modules
+      summary: Get the authenticated customer's active self-serve wash
+      description: |
+        Returns the latest active self-serve wash for the authenticated customer,
+        without requiring the frontend to know or poll a lane id.
+      operationId: getMyActiveSelfServeWash
+      responses:
+        '200':
+          description: Active self-serve wash details resolved
+          content:
+            application/json:
+              schema:
+                type: object
+                properties:
+                  lane_id:
+                    type: integer
+                  status:
+                    type: string
+                  in_progress:
+                    type: boolean
+                  elapsed_minutes:
+                    type: integer
+                  session:
+                    type: object
+                    nullable: true
+                  customer:
+                    type: object
+                    nullable: true
+                  vehicle:
+                    type: object
+                    nullable: true
+        '401':
+          $ref: '#/components/responses/Unauthorized'
+        '403':
+          $ref: '#/components/responses/Forbidden'
+        '404':
+          $ref: '#/components/responses/NotFound'
+
   /modules/self-serve/sessions:
     get:
       tags:
diff --git a/services/nginx/app/routes/moduleSelfServeRoute.php b/services/nginx/app/routes/moduleSelfServeRoute.php
index 9cd73fd7..3925a266 100644
--- a/services/nginx/app/routes/moduleSelfServeRoute.php
+++ b/services/nginx/app/routes/moduleSelfServeRoute.php
@@ -334,6 +334,23 @@ class moduleSelfServeRoute
             ]
         );
 
+        /** Modules > Self Serve > Lane > Wash > My active wash */
+        $this->get('/modules/self-serve/lane/wash/my-active-wash', function () {
+            global $response;
+
+            $customer_number = $this->requireMyActiveWashCustomerNumber();
+            $session = $this->findLatestActiveSelfServeSessionForCustomer($customer_number);
+            if (!$session->exists()) {
+                $response->error('No active self-serve wash found.', 404);
+            }
+
+            $response->success($this->buildActiveSelfServeSessionResponse($session));
+        },
+            [
+                'list_own_department_selfserve_vehicle_conditions' => 'View the authenticated customer\'s active self-serve wash',
+            ]
+        );
+
         /** Modules > Self Serve > Sessions */
         $this->get('/modules/self-serve/sessions', function () {
             global $response;
@@ -1307,6 +1324,188 @@ class moduleSelfServeRoute
         return null;
     }
 
+    private function requireMyActiveWashCustomerNumber(): int
+    {
+        global $response;
+
+        $user = (new authentication())->get_user();
+        if (!$user) {
+            $response->error('Authentication failed. Invalid or missing token.', 401);
+        }
+
+        if (!self::hasPermission(self::CUSTOMER_SELFSERVE_PERMISSION)) {
+            $this->emitForbidden([self::CUSTOMER_SELFSERVE_PERMISSION]);
+        }
+
+        $customer_number = $this->resolveEffectiveCustomerNumber();
+        if ($customer_number === null || $customer_number <= 0) {
+            $response->error('No customer number found for authenticated user.', 404);
+        }
+
+        return (int)$customer_number;
+    }
+
+    private function findLatestActiveSelfServeSessionForCustomer(int $customer_number): selfserve_wash_sessions_o
+    {
+        if ($customer_number <= 0) {
+            return new selfserve_wash_sessions_o();
+        }
+
+        $rows = (new selfserve_wash_sessions_o())->getFieldsWhere([
+            'customer_number' => $customer_number,
+            'completed_at' => null,
+            'deleted_at' => null,
+        ], ['id', 'status']);
+
+        $active_statuses = $this->activeSelfServeWashSessionStatusValues();
+        $rows = array_values(array_filter(
+            $rows,
+            static fn(array $row): bool => in_array((string)($row['status'] ?? ''), $active_statuses, true)
+        ));
+        if ($rows === []) {
+            return new selfserve_wash_sessions_o();
+        }
+
+        usort($rows, static fn(array $a, array $b): int => (int)$b['id'] <=> (int)$a['id']);
+        return (new selfserve_wash_sessions_o())->select((int)$rows[0]['id']);
+    }
+
+    /**
+     * @return array<int,string>
+     */
+    private function activeSelfServeWashSessionStatusValues(): array
+    {
+        return array_map(
+            static fn(selfserve_wash_session_status $status): string => $status->value,
+            [
+                selfserve_wash_session_status::MACHINE_RELAY_ENABLED,
+                selfserve_wash_session_status::READY_FOR_MACHINE_START,
+                selfserve_wash_session_status::MACHINE_STARTED,
+                selfserve_wash_session_status::PENDING_QUESTIONS,
+                selfserve_wash_session_status::MACHINE_NOT_ALLOWED,
+            ]
+        );
+    }
+
+    /**
+     * @return array<string,mixed>
+     */
+    private function buildActiveSelfServeSessionResponse(selfserve_wash_sessions_o $session): array
+    {
+        $lane_id = (int)$session->lane_id->value();
+        $customer_number = $session->customer_number->value() === null ? null : (int)$session->customer_number->value();
+        $vehicle_id = $session->vehicle_id->value() === null ? null : (int)$session->vehicle_id->value();
+        $session_reg = trim((string)$session->reg->value());
+        if ($session_reg === '') {
+            $session_reg = null;
+        }
+
+        $machine_start_triggered_at = $session->machine_start_triggered_at->value() === null ? null : (string)$session->machine_start_triggered_at->value();
+        $wash_started_at = $session->wash_started_at->value() === null ? null : (string)$session->wash_started_at->value();
+        if ($wash_started_at === null) {
+            $wash_started_at = $machine_start_triggered_at;
+        }
+
+        $machine_relay_enabled = (bool)$session->machine_relay_enabled->value();
+        $included_minutes = null;
+        if ($machine_relay_enabled) {
+            $included_minutes = (int)(new selfserve())->config->machine_wash_minutes_included->getVariableValue();
+            if ($included_minutes < 0) {
+                $included_minutes = 0;
+            }
+        }
+
+        return [
+            'lane_id' => $lane_id,
+            'status' => (string)$session->status->value(),
+            'in_progress' => true,
+            'elapsed_minutes' => $session->getElapsedMinutes(),
+            'session' => [
+                'id' => (int)$session->id,
+                'status' => (string)$session->status->value(),
+                'department_id' => $session->department_id->value() === null ? null : (int)$session->department_id->value(),
+                'lane_id' => $lane_id,
+                'reg' => $session_reg,
+                'customer_number' => $customer_number,
+                'vehicle_id' => $vehicle_id,
+                'vehicle_type_id' => $session->vehicle_type_id->value() === null ? null : (int)$session->vehicle_type_id->value(),
+                'included_minutes' => $included_minutes ?? 0,
+                'machine_type_id' => $session->machine_type_id->value() === null ? null : (int)$session->machine_type_id->value(),
+                'machine_relay_enabled' => $machine_relay_enabled,
+                'machine_relay_enabled_at' => $session->machine_relay_enabled_at->value() === null ? null : (string)$session->machine_relay_enabled_at->value(),
+                'machine_start_triggered' => (bool)$session->machine_start_triggered->value(),
+                'machine_start_triggered_at' => $machine_start_triggered_at,
+                'wash_started_at' => $wash_started_at,
+                'created_at' => (string)$session->created_at->value(),
+                'updated_at' => $session->updated_at->value() === null ? null : (string)$session->updated_at->value(),
+            ],
+            'customer' => $this->buildInProgressWashCustomerPayload($customer_number),
+            'vehicle' => $this->buildInProgressWashVehiclePayload($vehicle_id, $session_reg),
+        ];
+    }
+
+    /**
+     * @return array<string,mixed>|null
+     */
+    private function buildInProgressWashCustomerPayload(?int $customer_number): ?array
+    {
+        if ($customer_number === null || $customer_number <= 0) {
+            return null;
+        }
+
+        $customer_obj = (new users_o())->getUserByCustomerNumber($customer_number);
+        if ($customer_obj->exists()) {
+            return [
+                'id' => (int)$customer_obj->id,
+                'customer_number' => $customer_number,
+                'display_name' => $customer_obj->display_name->value() === null ? null : (string)$customer_obj->display_name->value(),
+                'email' => $customer_obj->email->value() === null ? null : (string)$customer_obj->email->value(),
+                'phone_country_code' => $customer_obj->phone_country_code->value() === null ? null : (int)$customer_obj->phone_country_code->value(),
+                'phone' => $customer_obj->phone->value() === null ? null : (string)$customer_obj->phone->value(),
+            ];
+        }
+
+        return [
+            'id' => null,
+            'customer_number' => $customer_number,
+            'display_name' => null,
+            'email' => null,
+            'phone_country_code' => null,
+            'phone' => null,
+        ];
+    }
+
+    /**
+     * @return array<string,mixed>|null
+     */
+    private function buildInProgressWashVehiclePayload(?int $vehicle_id, ?string $reg): ?array
+    {
+        $vehicle_obj = null;
+        if ($vehicle_id !== null && $vehicle_id > 0) {
+            $tmp_vehicle = (new customer_vehicles_o())->select($vehicle_id);
+            if ($tmp_vehicle->exists()) {
+                $vehicle_obj = $tmp_vehicle;
+            }
+        }
+        if ($vehicle_obj === null && $reg !== null && trim($reg) !== '') {
+            $tmp_vehicle = (new customer_vehicles_o())->selectByPlate(trim($reg));
+            if ($tmp_vehicle->exists()) {
+                $vehicle_obj = $tmp_vehicle;
+            }
+        }
+        if ($vehicle_obj === null) {
+            return null;
+        }
+
+        return [
+            'id' => (int)$vehicle_obj->id,
+            'customer_id' => (int)$vehicle_obj->customer_id->value(),
+            'type' => (int)$vehicle_obj->type->value(),
+            'reg' => (string)$vehicle_obj->reg->value(),
+            'reference' => $vehicle_obj->reference->value() === null ? null : (string)$vehicle_obj->reference->value(),
+        ];
+    }
+
     /**
      * @param array<string,mixed> $status
      * @param array<string,mixed> $extra
diff --git a/services/nginx/app/tests/Api/SelfserveLaneWashInProgressApiTest.php b/services/nginx/app/tests/Api/SelfserveLaneWashInProgressApiTest.php
index 8e6cd284..3a647451 100644
--- a/services/nginx/app/tests/Api/SelfserveLaneWashInProgressApiTest.php
+++ b/services/nginx/app/tests/Api/SelfserveLaneWashInProgressApiTest.php
@@ -10,6 +10,14 @@ it('requires authentication before checking in-progress wash permissions', funct
         ->assertMessage('Authentication failed. Invalid or missing token.');
 });
 
+it('requires authentication before checking the current customers active self-serve wash', function (): void {
+    $response = api_client()->get('/modules/self-serve/lane/wash/my-active-wash');
+
+    $response
+        ->assertStatus(401)
+        ->assertMessage('Authentication failed. Invalid or missing token.');
+});
+
 it('reports both elevated and customer self-serve permissions when lane polling is not allowed', function (): void {
     $session = api_fixtures()->createUserSession([]);
 
@@ -26,6 +34,18 @@ it('reports both elevated and customer self-serve permissions when lane polling
         ]);
 });
 
+it('requires customer self-serve permission before checking my active wash', function (): void {
+    $session = api_fixtures()->createUserSession([]);
+
+    $response = api_client()->get('/modules/self-serve/lane/wash/my-active-wash', $session['headers']);
+
+    $response
+        ->assertStatus(403)
+        ->assertMissingPermissions([
+            'list_own_department_selfserve_vehicle_conditions',
+        ]);
+});
+
 it('allows customer self-serve permission to view their own in-progress wash details', function (): void {
     $group = api_fixtures()->createGroup([], [
         'list_own_department_selfserve_vehicle_conditions',
@@ -51,6 +71,46 @@ it('allows customer self-serve permission to view their own in-progress wash det
         ->and($response->data()['vehicle']['reg'] ?? null)->toBe($scenario['vehicle']['reg']);
 });
 
+it('returns the authenticated customers active self-serve wash without requiring a lane id', function (): void {
+    $group = api_fixtures()->createGroup([], [
+        'list_own_department_selfserve_vehicle_conditions',
+    ]);
+    $scenario = api_fixtures()->createSelfServeScenario([
+        'customer' => [
+            'group_id' => $group['id'],
+        ],
+    ]);
+    $token = api_fixtures()->createAuthToken((int)$scenario['customer']['id']);
+
+    $response = api_client()->get(
+        '/modules/self-serve/lane/wash/my-active-wash',
+        api_fixtures()->bearerHeaders($token)
+    );
+
+    $response
+        ->assertStatus(200)
+        ->assertSuccess(true);
+
+    expect($response->data()['in_progress'] ?? null)->toBeTrue()
+        ->and($response->data()['lane_id'] ?? null)->toBe((int)$scenario['lane']['id'])
+        ->and($response->data()['session']['id'] ?? null)->toBe((int)$scenario['session']['id'])
+        ->and($response->data()['session']['lane_id'] ?? null)->toBe((int)$scenario['lane']['id'])
+        ->and($response->data()['session']['customer_number'] ?? null)->toBe((int)$scenario['customer']['customer_number'])
+        ->and($response->data()['vehicle']['reg'] ?? null)->toBe($scenario['vehicle']['reg']);
+});
+
+it('returns 404 when the authenticated customer has no active self-serve wash', function (): void {
+    $session = api_fixtures()->createUserSession([
+        'list_own_department_selfserve_vehicle_conditions',
+    ]);
+
+    $response = api_client()->get('/modules/self-serve/lane/wash/my-active-wash', $session['headers']);
+
+    $response
+        ->assertStatus(404)
+        ->assertMessage('No active self-serve wash found.');
+});
+
 it('redacts another customers in-progress wash from customer self-serve lane polling', function (): void {
     $scenario = api_fixtures()->createSelfServeScenario();
     $otherSession = api_fixtures()->createUserSession([
diff --git a/services/nginx/app/tests/Unit/Selfserve/SelfserveOpenApiSpecTest.php b/services/nginx/app/tests/Unit/Selfserve/SelfserveOpenApiSpecTest.php
index 4112dfd1..3d937789 100644
--- a/services/nginx/app/tests/Unit/Selfserve/SelfserveOpenApiSpecTest.php
+++ b/services/nginx/app/tests/Unit/Selfserve/SelfserveOpenApiSpecTest.php
@@ -52,6 +52,7 @@ it('documents self-serve machine type, eligibility, summary, and webhook endpoin
     expect($content)->toContain('/relay/button/press/post:');
     expect($content)->toContain('/relay/machine/on/post:');
     expect($content)->toContain('/modules/self-serve/lane/wash/in-progress:');
+    expect($content)->toContain('/modules/self-serve/lane/wash/my-active-wash:');
     expect($content)->toContain('/modules/self-serve/lane/relay/machine/status:');
     expect($content)->toContain('/modules/self-serve/lane/relay/machine/set:');
     expect($content)->toContain('/modules/self-serve/lane/gate/open:');
diff --git a/services/nginx/app/tests/Unit/Selfserve/SelfserveRouteWiringTest.php b/services/nginx/app/tests/Unit/Selfserve/SelfserveRouteWiringTest.php
index b742cbea..a895f77f 100644
--- a/services/nginx/app/tests/Unit/Selfserve/SelfserveRouteWiringTest.php
+++ b/services/nginx/app/tests/Unit/Selfserve/SelfserveRouteWiringTest.php
@@ -286,9 +286,12 @@ it('wires in-progress self-serve wash details endpoint', function (): void {
 
     expect($moduleSelfServeRoute)->not->toBeFalse();
     expect($moduleSelfServeRoute)->toContain('/modules/self-serve/lane/wash/in-progress');
+    expect($moduleSelfServeRoute)->toContain('/modules/self-serve/lane/wash/my-active-wash');
     expect($moduleSelfServeRoute)->toContain('modules_selfserve_lane_wash_in_progress_view');
     expect($moduleSelfServeRoute)->toContain('list_own_department_selfserve_vehicle_conditions');
     expect($moduleSelfServeRoute)->toContain('requireInProgressWashDetailsAccess($lane_id)');
+    expect($moduleSelfServeRoute)->toContain('findLatestActiveSelfServeSessionForCustomer($customer_number)');
+    expect($moduleSelfServeRoute)->toContain('buildActiveSelfServeSessionResponse($session)');
     expect($moduleSelfServeRoute)->toContain('(new department_lanes_o())->select($lane_id)');
     expect($moduleSelfServeRoute)->toContain('self::requireDepartmentAccess((string)$department_lane->department->value())');
     expect($moduleSelfServeRoute)->toContain('scopeInProgressWashResponseForCustomer');