New York Consolidated Laws, General Obligations Law - GOB § 15-701. Surety not discharged by failure or refusal by creditor to sue principal debtor

Unless otherwise agreed between the parties in writing, the failure or refusal by a creditor, after a demand by a person bound as surety, to bring an action against a principal debtor upon a contract hereafter made or an obligation hereafter created for the payment of money or the performance of any act shall not discharge such surety.