diff --git a/app/Http/Requests/AccountFormRequest.php b/app/Http/Requests/AccountFormRequest.php
index 9bc9a38fa3..8a143f45bc 100644
--- a/app/Http/Requests/AccountFormRequest.php
+++ b/app/Http/Requests/AccountFormRequest.php
@@ -94,11 +94,11 @@ class AccountFormRequest extends Request
         $ccPaymentTypes = implode(',', array_keys(config('firefly.ccTypes')));
         $rules          = [
             'name'                               => 'required|min:1|uniqueAccountForUser',
-            'opening_balance'                    => 'numeric|required_with:opening_balance_date|nullable',
+            'opening_balance'                    => 'numeric|required_with:opening_balance_date|nullable|max:1000000000',
             'opening_balance_date'               => 'date|required_with:opening_balance|nullable',
             'iban'                               => ['iban', 'nullable', new UniqueIban(null, $this->string('objectType'))],
             'BIC'                                => 'bic|nullable',
-            'virtual_balance'                    => 'numeric|nullable',
+            'virtual_balance'                    => 'numeric|nullable|max:1000000000',
             'currency_id'                        => 'exists:transaction_currencies,id',
             'account_number'                     => 'between:1,255|uniqueAccountNumberForUser|nullable',
             'account_role'                       => 'in:' . $accountRoles,
@@ -111,7 +111,7 @@ class AccountFormRequest extends Request
         ];
 
         if ('liabilities' === $this->get('objectType')) {
-            $rules['opening_balance']      = ['numeric', 'required'];
+            $rules['opening_balance']      = ['numeric', 'required','max:1000000000'];
             $rules['opening_balance_date'] = 'date|required';
         }
 
diff --git a/app/Http/Requests/BudgetIncomeRequest.php b/app/Http/Requests/BudgetIncomeRequest.php
index e7b911e20f..af531bfab6 100644
--- a/app/Http/Requests/BudgetIncomeRequest.php
+++ b/app/Http/Requests/BudgetIncomeRequest.php
@@ -49,7 +49,7 @@ class BudgetIncomeRequest extends Request
     {
         // fixed
         return [
-            'amount' => 'numeric|required|min:0',
+            'amount' => 'numeric|required|min:0|max:1000000000',
             'start'  => 'required|date|before:end',
             'end'    => 'required|date|after:start',
         ];
diff --git a/app/Http/Requests/NewUserFormRequest.php b/app/Http/Requests/NewUserFormRequest.php
index 343b36403d..68113fb60b 100644
--- a/app/Http/Requests/NewUserFormRequest.php
+++ b/app/Http/Requests/NewUserFormRequest.php
@@ -50,9 +50,9 @@ class NewUserFormRequest extends Request
         // fixed
         return [
             'bank_name'                            => 'required|between:1,200',
-            'bank_balance'                         => 'required|numeric',
-            'savings_balance'                      => 'numeric',
-            'credit_card_limit'                    => 'numeric',
+            'bank_balance'                         => 'required|numeric|max:1000000000',
+            'savings_balance'                      => 'numeric|max:1000000000',
+            'credit_card_limit'                    => 'numeric|max: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/ReconciliationStoreRequest.php b/app/Http/Requests/ReconciliationStoreRequest.php
index 1113266f04..7a52cc109c 100644
--- a/app/Http/Requests/ReconciliationStoreRequest.php
+++ b/app/Http/Requests/ReconciliationStoreRequest.php
@@ -77,9 +77,9 @@ class ReconciliationStoreRequest extends Request
         return [
             'start'        => 'required|date',
             'end'          => 'required|date',
-            'startBalance' => 'numeric',
-            'endBalance'   => 'numeric',
-            'difference'   => 'required|numeric',
+            'startBalance' => 'numeric|max:1000000000',
+            'endBalance'   => 'numeric|max:1000000000',
+            'difference'   => 'required|numeric|max:1000000000',
             'journals'     => [new ValidJournals],
             'reconcile'    => 'required|in:create,nothing',
         ];
diff --git a/app/Http/Requests/RecurrenceFormRequest.php b/app/Http/Requests/RecurrenceFormRequest.php
index 572cefdc9b..7875b45fad 100644
--- a/app/Http/Requests/RecurrenceFormRequest.php
+++ b/app/Http/Requests/RecurrenceFormRequest.php
@@ -160,7 +160,7 @@ class RecurrenceFormRequest extends Request
             'transaction_description' => 'required|between:1,255',
             'transaction_type'        => 'required|in:withdrawal,deposit,transfer',
             'transaction_currency_id' => 'required|exists:transaction_currencies,id',
-            'amount'                  => 'numeric|required|more:0',
+            'amount'                  => 'numeric|required|more:0|max:1000000000',
             // mandatory account info:
             'source_id'               => 'numeric|belongsToUser:accounts,id|nullable',
             'source_name'             => 'between:1,255|nullable',
@@ -168,7 +168,7 @@ class RecurrenceFormRequest extends Request
             'destination_name'        => 'between:1,255|nullable',
 
             // foreign amount data:
-            'foreign_amount'          => 'nullable|more:0',
+            'foreign_amount'          => 'nullable|more:0|max:1000000000',
 
             // optional fields:
             'budget_id'               => 'mustExist:budgets,id|belongsToUser:budgets,id|nullable',