diff --git a/app/Http/Requests/AccountFormRequest.php b/app/Http/Requests/AccountFormRequest.php
index edf8837d12..8f56d1b9b6 100644
--- a/app/Http/Requests/AccountFormRequest.php
+++ b/app/Http/Requests/AccountFormRequest.php
@@ -101,11 +101,11 @@ class AccountFormRequest extends FormRequest
         $ccPaymentTypes = implode(',', array_keys(config('firefly.ccTypes')));
         $rules          = [
             'name'                               => 'required|max:1024|min:1|uniqueAccountForUser',
-            'opening_balance'                    => 'numeric|nullable|max:1000000000',
+            'opening_balance'                    => 'numeric|nullable|max:1000000000|min:-1000000000',
             'opening_balance_date'               => 'date|required_with:opening_balance|nullable',
             'iban'                               => ['iban', 'nullable', new UniqueIban(null, $this->convertString('objectType'))],
             'BIC'                                => 'bic|nullable',
-            'virtual_balance'                    => 'numeric|nullable|max:1000000000',
+            'virtual_balance'                    => 'numeric|nullable|max:1000000000|min:-1000000000',
             'currency_id'                        => 'exists:transaction_currencies,id',
             'account_number'                     => 'between:1,255|uniqueAccountNumberForUser|nullable',
             'account_role'                       => 'in:'.$accountRoles,
diff --git a/app/Http/Requests/NewUserFormRequest.php b/app/Http/Requests/NewUserFormRequest.php
index 4f10def9ef..2d4c3396b8 100644
--- a/app/Http/Requests/NewUserFormRequest.php
+++ b/app/Http/Requests/NewUserFormRequest.php
@@ -43,9 +43,9 @@ class NewUserFormRequest extends FormRequest
         // fixed
         return [
             'bank_name'                            => 'required|between:1,200',
-            'bank_balance'                         => 'required|numeric|max:1000000000',
-            'savings_balance'                      => 'numeric|max:1000000000',
-            'credit_card_limit'                    => 'numeric|max:1000000000',
+            'bank_balance'                         => 'required|numeric|max:1000000000|min:-1000000000',
+            'savings_balance'                      => 'numeric|max:1000000000|min:-1000000000',
+            'credit_card_limit'                    => 'numeric|max:1000000000|min:-1000000000',
             'amount_currency_id_bank_balance'      => 'exists:transaction_currencies,id',
             'amount_currency_id_savings_balance'   => 'exists:transaction_currencies,id',
             'amount_currency_id_credit_card_limit' => 'exists:transaction_currencies,id',
diff --git a/app/Http/Requests/PiggyBankStoreRequest.php b/app/Http/Requests/PiggyBankStoreRequest.php
index aa769fbbba..03be27f855 100644
--- a/app/Http/Requests/PiggyBankStoreRequest.php
+++ b/app/Http/Requests/PiggyBankStoreRequest.php
@@ -59,7 +59,7 @@ class PiggyBankStoreRequest extends FormRequest
         return [
             'name'         => 'required|between:1,255|uniquePiggyBankForUser',
             'account_id'   => 'required|belongsToUser:accounts',
-            'targetamount' => 'nullable|numeric|max:1000000000',
+            'targetamount' => 'nullable|numeric|max:1000000000|min:-1000000000',
             'startdate'    => 'date',
             'targetdate'   => 'date|nullable',
             'order'        => 'integer|min:1',
diff --git a/app/Http/Requests/PiggyBankUpdateRequest.php b/app/Http/Requests/PiggyBankUpdateRequest.php
index 985fbc8cf9..a67170dcc5 100644
--- a/app/Http/Requests/PiggyBankUpdateRequest.php
+++ b/app/Http/Requests/PiggyBankUpdateRequest.php
@@ -63,7 +63,7 @@ class PiggyBankUpdateRequest extends FormRequest
         return [
             'name'         => sprintf('required|between:1,255|uniquePiggyBankForUser:%d', $piggy->id),
             'account_id'   => 'required|belongsToUser:accounts',
-            'targetamount' => 'nullable|numeric|max:1000000000',
+            'targetamount' => 'nullable|numeric|max:1000000000|min:-1000000000',
             'startdate'    => 'date',
             'targetdate'   => 'date|nullable',
             'order'        => 'integer|max:65536|min:1',
diff --git a/app/Http/Requests/ReconciliationStoreRequest.php b/app/Http/Requests/ReconciliationStoreRequest.php
index 0b095353cb..70e9c42a15 100644
--- a/app/Http/Requests/ReconciliationStoreRequest.php
+++ b/app/Http/Requests/ReconciliationStoreRequest.php
@@ -67,9 +67,9 @@ class ReconciliationStoreRequest extends FormRequest
         return [
             'start'        => 'required|date',
             'end'          => 'required|date',
-            'startBalance' => 'numeric|max:1000000000',
-            'endBalance'   => 'numeric|max:1000000000',
-            'difference'   => 'required|numeric|max:1000000000',
+            'startBalance' => 'numeric|max:1000000000|min:-1000000000',
+            'endBalance'   => 'numeric|max:1000000000|min:-1000000000',
+            'difference'   => 'required|numeric|max:1000000000|min:-1000000000',
             'journals'     => [new ValidJournals()],
             'reconcile'    => 'required|in:create,nothing',
         ];