diff --git a/src/app/Http/Controllers/API/V4/Admin/DiscountsController.php b/src/app/Http/Controllers/API/V4/Admin/DiscountsController.php
new file mode 100644
--- /dev/null
+++ b/src/app/Http/Controllers/API/V4/Admin/DiscountsController.php
@@ -0,0 +1,42 @@
+<?php
+
+namespace App\Http\Controllers\API\V4\Admin;
+
+use App\Discount;
+use App\Http\Controllers\Controller;
+
+class DiscountsController extends Controller
+{
+    /**
+     * Returns (active) discounts defined in the system.
+     *
+     * @return \Illuminate\Http\JsonResponse JSON response
+     */
+    public function index()
+    {
+        $discounts = [];
+
+        Discount::where('active', true)->orderBy('discount')->get()
+            ->map(function ($discount) use (&$discounts) {
+                $label = $discount->discount . '% - ' . $discount->description;
+
+                if ($discount->code) {
+                    $label .= " [{$discount->code}]";
+                }
+
+                $discounts[] = [
+                    'id' => $discount->id,
+                    'discount' => $discount->discount,
+                    'code' => $discount->code,
+                    'description' => $discount->description,
+                    'label' => $label,
+                ];
+            });
+
+        return response()->json([
+                'status' => 'success',
+                'list' => $discounts,
+                'count' => count($discounts),
+        ]);
+    }
+}
diff --git a/src/app/Http/Controllers/API/V4/Admin/WalletsController.php b/src/app/Http/Controllers/API/V4/Admin/WalletsController.php
--- a/src/app/Http/Controllers/API/V4/Admin/WalletsController.php
+++ b/src/app/Http/Controllers/API/V4/Admin/WalletsController.php
@@ -2,6 +2,48 @@
 
 namespace App\Http\Controllers\API\V4\Admin;
 
+use App\Discount;
+use App\Wallet;
+use Illuminate\Http\Request;
+
 class WalletsController extends \App\Http\Controllers\API\V4\WalletsController
 {
+    /**
+     * Update wallet data.
+     *
+     * @param \Illuminate\Http\Request $request The API request.
+     * @params string                  $id      Wallet identifier
+     *
+     * @return \Illuminate\Http\JsonResponse The response
+     */
+    public function update(Request $request, $id)
+    {
+        $wallet = Wallet::find($id);
+
+        if (empty($wallet)) {
+            return $this->errorResponse(404);
+        }
+
+        if (array_key_exists('discount', $request->input())) {
+            if (empty($request->discount)) {
+                $wallet->discount()->dissociate();
+                $wallet->save();
+            } elseif ($discount = Discount::find($request->discount)) {
+                $wallet->discount()->associate($discount);
+                $wallet->save();
+            }
+        }
+
+        $response = $wallet->toArray();
+
+        if ($wallet->discount) {
+            $response['discount'] = $wallet->discount->discount;
+            $response['discount_description'] = $wallet->discount->description;
+        }
+
+        $response['status'] = 'success';
+        $response['message'] = \trans('app.wallet-update-success');
+
+        return response()->json($response);
+    }
 }
diff --git a/src/app/Http/Controllers/API/V4/WalletsController.php b/src/app/Http/Controllers/API/V4/WalletsController.php
--- a/src/app/Http/Controllers/API/V4/WalletsController.php
+++ b/src/app/Http/Controllers/API/V4/WalletsController.php
@@ -13,7 +13,7 @@
     /**
      * Display a listing of the resource.
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function index()
     {
@@ -23,7 +23,7 @@
     /**
      * Show the form for creating a new resource.
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function create()
     {
@@ -35,7 +35,7 @@
      *
      * @param \Illuminate\Http\Request $request
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function store(Request $request)
     {
@@ -47,7 +47,7 @@
      *
      * @param int $id
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function show($id)
     {
@@ -59,7 +59,7 @@
      *
      * @param int $id
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function edit($id)
     {
@@ -72,7 +72,7 @@
      * @param \Illuminate\Http\Request $request
      * @param int                      $id
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function update(Request $request, $id)
     {
@@ -84,7 +84,7 @@
      *
      * @param int $id
      *
-     * @return \Illuminate\Http\Response
+     * @return \Illuminate\Http\JsonResponse
      */
     public function destroy($id)
     {
diff --git a/src/resources/lang/en/app.php b/src/resources/lang/en/app.php
--- a/src/resources/lang/en/app.php
+++ b/src/resources/lang/en/app.php
@@ -27,4 +27,6 @@
 
     'search-foundxdomains' => ':x domains have been found.',
     'search-foundxusers' => ':x user accounts have been found.',
+
+    'wallet-update-success' => 'User wallet updated successfully.',
 ];
diff --git a/src/resources/vue/Admin/User.vue b/src/resources/vue/Admin/User.vue
--- a/src/resources/vue/Admin/User.vue
+++ b/src/resources/vue/Admin/User.vue
@@ -110,7 +110,7 @@
                                 <div class="col-sm-10">
                                     <span class="form-control-plaintext" id="discount">
                                         <span>{{ wallet_discount ? (wallet_discount + '% - ' + wallet_discount_description) : 'none' }}</span>
-                                        <button type="button" class="btn btn-secondary btn-sm">Edit</button>
+                                        <button type="button" class="btn btn-secondary btn-sm" @click="discountEdit">Edit</button>
                                     </span>
                                 </div>
                             </div>
@@ -223,6 +223,33 @@
                 </div>
             </div>
         </div>
+
+        <div id="discount-dialog" class="modal" tabindex="-1" role="dialog">
+            <div class="modal-dialog" role="document">
+                <div class="modal-content">
+                    <div class="modal-header">
+                        <h5 class="modal-title">Account discount</h5>
+                        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
+                            <span aria-hidden="true">&times;</span>
+                        </button>
+                    </div>
+                    <div class="modal-body">
+                        <p class="form-group">
+                            <select v-model="wallet_discount_id" class="custom-select">
+                                <option value="">- none -</option>
+                                <option v-for="item in discounts" :value="item.id" :key="item.id">{{ item.label }}</option>
+                            </select>
+                        </p>
+                    </div>
+                    <div class="modal-footer">
+                        <button type="button" class="btn btn-secondary modal-cancel" data-dismiss="modal">Cancel</button>
+                        <button type="button" class="btn btn-primary modal-action" @click="submitDiscount()">
+                            <svg-icon icon="check"></svg-icon> Submit
+                        </button>
+                    </div>
+                </div>
+            </div>
+        </div>
     </div>
 </template>
 
@@ -240,8 +267,10 @@
                 balance: 0,
                 discount: 0,
                 discount_description: '',
+                discounts: [],
                 wallet_discount: 0,
                 wallet_discount_description: '',
+                wallet_discount_id: '',
                 domains: [],
                 skus: [],
                 users: [],
@@ -281,6 +310,7 @@
                     })
 
                     this.wallet_discount = this.user.wallets[0].discount
+                    this.wallet_discount_id = this.user.wallets[0].discount_id || ''
                     this.wallet_discount_description = this.user.wallets[0].discount_description
 
                     // Create subscriptions list
@@ -293,6 +323,8 @@
                                     let item = {
                                         id: sku.id,
                                         name: sku.name,
+                                        cost: sku.cost,
+                                        units: count - sku.units_free,
                                         price: this.price(sku.cost, count - sku.units_free)
                                     }
 
@@ -329,6 +361,21 @@
             })
         },
         methods: {
+            discountEdit() {
+                $('#discount-dialog')
+                    .on('shown.bs.modal', (e, a) => {
+                        $(e.target).find('select').focus()
+                    })
+                    .modal()
+
+                if (!this.discounts.length) {
+                    // Fetch discounts
+                    axios.get('/api/v4/discounts')
+                        .then(response => {
+                            this.discounts = response.data.list
+                        })
+                }
+            },
             price(cost, units = 1) {
                 let index = ''
 
@@ -342,7 +389,30 @@
                 }
 
                 return this.$root.price(cost * units) + '/month' + index
-            }
+            },
+            submitDiscount() {
+                let dialog = $('#discount-dialog').modal('hide')
+
+                axios.put('/api/v4/wallets/' + this.user.wallets[0].id, { discount: this.wallet_discount_id })
+                    .then(response => {
+                        if (response.data.status == 'success') {
+                            this.$toastr('success', response.data.message)
+                            this.wallet_discount = response.data.discount
+                            this.wallet_discount_id = response.data.discount_id || ''
+                            this.wallet_discount_description = response.data.discount_description
+
+                            // Update prices in Subscriptions tab
+                            if (this.user.wallet.id == response.data.id) {
+                                this.discount = this.wallet_discount
+                                this.discount_description = this.wallet_discount_description
+
+                                this.skus.forEach(sku => {
+                                    sku.price = this.price(sku.cost, sku.units)
+                                })
+                            }
+                        }
+                    })
+            },
         }
     }
 </script>
diff --git a/src/routes/api.php b/src/routes/api.php
--- a/src/routes/api.php
+++ b/src/routes/api.php
@@ -94,5 +94,6 @@
         Route::apiResource('skus', API\V4\Admin\SkusController::class);
         Route::apiResource('users', API\V4\Admin\UsersController::class);
         Route::apiResource('wallets', API\V4\Admin\WalletsController::class);
+        Route::apiResource('discounts', API\V4\Admin\DiscountsController::class);
     }
 );
diff --git a/src/tests/Browser/Admin/UserTest.php b/src/tests/Browser/Admin/UserTest.php
--- a/src/tests/Browser/Admin/UserTest.php
+++ b/src/tests/Browser/Admin/UserTest.php
@@ -4,6 +4,7 @@
 
 use App\Discount;
 use Tests\Browser;
+use Tests\Browser\Components\Dialog;
 use Tests\Browser\Components\Toast;
 use Tests\Browser\Pages\Admin\User as UserPage;
 use Tests\Browser\Pages\Dashboard;
@@ -339,4 +340,63 @@
                 });
         });
     }
+
+    /**
+     * Test editing wallet discount
+     *
+     * @depends testUserInfo2
+     */
+    public function testWalletDiscount(): void
+    {
+        $this->browse(function (Browser $browser) {
+            $john = $this->getTestUser('john@kolab.org');
+
+            $browser->visit(new UserPage($john->id))
+                ->pause(100)
+                ->click('@user-finances #discount button')
+                // Test dialog content, and closing it with Cancel button
+                ->with(new Dialog('#discount-dialog'), function (Browser $browser) {
+                    $browser->assertSeeIn('@title', 'Account discount')
+                        ->assertFocused('@body select')
+                        ->assertSelected('@body select', '')
+                        ->assertSeeIn('@button-cancel', 'Cancel')
+                        ->assertSeeIn('@button-action', 'Submit')
+                        ->click('@button-cancel');
+                })
+                ->assertMissing('#discount-dialog')
+                ->click('@user-finances #discount button')
+                // Change the discount
+                ->with(new Dialog('#discount-dialog'), function (Browser $browser) {
+                    $browser->click('@body select')
+                        ->click('@body select option:nth-child(2)')
+                        ->click('@button-action');
+                })
+                ->assertToast(Toast::TYPE_SUCCESS, '', 'User wallet updated successfully.')
+                ->assertSeeIn('#discount span', '10% - Test voucher')
+                ->click('@nav #tab-subscriptions')
+                ->with('@user-subscriptions', function (Browser $browser) {
+                    $browser->assertSeeIn('table tbody tr:nth-child(1) td:last-child', '3,99 CHF/month¹')
+                        ->assertSeeIn('table tbody tr:nth-child(2) td:last-child', '0,00 CHF/month¹')
+                        ->assertSeeIn('table tbody tr:nth-child(3) td:last-child', '4,99 CHF/month¹')
+                        ->assertSeeIn('table + .hint', '¹ applied discount: 10% - Test voucher');
+                })
+                // Change back to 'none'
+                ->click('@nav #tab-finances')
+                ->click('@user-finances #discount button')
+                ->with(new Dialog('#discount-dialog'), function (Browser $browser) {
+                    $browser->click('@body select')
+                        ->click('@body select option:nth-child(1)')
+                        ->click('@button-action');
+                })
+                ->assertToast(Toast::TYPE_SUCCESS, '', 'User wallet updated successfully.')
+                ->assertSeeIn('#discount span', 'none')
+                ->click('@nav #tab-subscriptions')
+                ->with('@user-subscriptions', function (Browser $browser) {
+                    $browser->assertSeeIn('table tbody tr:nth-child(1) td:last-child', '4,44 CHF/month')
+                        ->assertSeeIn('table tbody tr:nth-child(2) td:last-child', '0,00 CHF/month')
+                        ->assertSeeIn('table tbody tr:nth-child(3) td:last-child', '5,55 CHF/month')
+                        ->assertMissing('table + .hint');
+                });
+        });
+    }
 }
diff --git a/src/tests/Feature/Controller/Admin/DiscountsTest.php b/src/tests/Feature/Controller/Admin/DiscountsTest.php
new file mode 100644
--- /dev/null
+++ b/src/tests/Feature/Controller/Admin/DiscountsTest.php
@@ -0,0 +1,61 @@
+<?php
+
+namespace Tests\Feature\Controller\Admin;
+
+use App\Discount;
+use Tests\TestCase;
+
+class DiscountsTest extends TestCase
+{
+    /**
+     * {@inheritDoc}
+     */
+    public function setUp(): void
+    {
+        parent::setUp();
+        self::useAdminUrl();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function tearDown(): void
+    {
+        parent::tearDown();
+    }
+
+    /**
+     * Test listing discounts (/api/v4/discounts)
+     */
+    public function testIndex(): void
+    {
+        $user = $this->getTestUser('john@kolab.org');
+        $admin = $this->getTestUser('jeroen@jeroen.jeroen');
+
+        // Non-admin user
+        $response = $this->actingAs($user)->get("api/v4/discounts");
+        $response->assertStatus(403);
+
+        // Admin user
+        $response = $this->actingAs($admin)->get("api/v4/discounts");
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $discount_test = Discount::where('code', 'TEST')->first();
+        $discount_free = Discount::where('discount', 100)->first();
+
+        $this->assertSame(3, $json['count']);
+        $this->assertSame($discount_test->id, $json['list'][0]['id']);
+        $this->assertSame($discount_test->discount, $json['list'][0]['discount']);
+        $this->assertSame($discount_test->code, $json['list'][0]['code']);
+        $this->assertSame($discount_test->description, $json['list'][0]['description']);
+        $this->assertSame('10% - Test voucher [TEST]', $json['list'][0]['label']);
+
+        $this->assertSame($discount_free->id, $json['list'][2]['id']);
+        $this->assertSame($discount_free->discount, $json['list'][2]['discount']);
+        $this->assertSame($discount_free->code, $json['list'][2]['code']);
+        $this->assertSame($discount_free->description, $json['list'][2]['description']);
+        $this->assertSame('100% - Free Account', $json['list'][2]['label']);
+    }
+}
diff --git a/src/tests/Feature/Controller/Admin/WalletsTest.php b/src/tests/Feature/Controller/Admin/WalletsTest.php
new file mode 100644
--- /dev/null
+++ b/src/tests/Feature/Controller/Admin/WalletsTest.php
@@ -0,0 +1,70 @@
+<?php
+
+namespace Tests\Feature\Controller\Admin;
+
+use App\Discount;
+use Tests\TestCase;
+
+class WalletsTest extends TestCase
+{
+    /**
+     * {@inheritDoc}
+     */
+    public function setUp(): void
+    {
+        parent::setUp();
+        self::useAdminUrl();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function tearDown(): void
+    {
+        parent::tearDown();
+    }
+
+    /**
+     * Test updating a wallet (PUT /api/v4/wallets/:id)
+     */
+    public function testUpdate(): void
+    {
+        $user = $this->getTestUser('john@kolab.org');
+        $admin = $this->getTestUser('jeroen@jeroen.jeroen');
+        $wallet = $user->wallets()->first();
+        $discount = Discount::where('code', 'TEST')->first();
+
+        // Non-admin user
+        $response = $this->actingAs($user)->put("api/v4/wallets/{$wallet->id}", []);
+        $response->assertStatus(403);
+
+        // Admin user - setting a discount
+        $post = ['discount' => $discount->id];
+        $response = $this->actingAs($admin)->put("api/v4/wallets/{$wallet->id}", $post);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+        $this->assertSame('User wallet updated successfully.', $json['message']);
+        $this->assertSame($wallet->id, $json['id']);
+        $this->assertSame($discount->discount, $json['discount']);
+        $this->assertSame($discount->id, $json['discount_id']);
+        $this->assertSame($discount->description, $json['discount_description']);
+        $this->assertSame($discount->id, $wallet->fresh()->discount->id);
+
+        // Admin user - removing a discount
+        $post = ['discount' => null];
+        $response = $this->actingAs($admin)->put("api/v4/wallets/{$wallet->id}", $post);
+        $response->assertStatus(200);
+
+        $json = $response->json();
+
+        $this->assertSame('success', $json['status']);
+        $this->assertSame('User wallet updated successfully.', $json['message']);
+        $this->assertSame($wallet->id, $json['id']);
+        $this->assertSame(null, $json['discount_id']);
+        $this->assertTrue(empty($json['discount_description']));
+        $this->assertSame(null, $wallet->fresh()->discount);
+    }
+}