There are two ways arbitration is triggered in Washington- by contractual agreement or by the mandatory arbitration rules in the district in which the dispute is located. It is extremely common for real estate purchase contracts to contain an arbitration clause, so you should be prepared to review the real estate purchase contract to see if this applies. Additionally, most counties in Washington, unless the claim is exempt for some other reason, disputes in the amount of $50,000 or less are subject to mandatory arbitration under the guidance of the court system, so your case may also be subject to mandatory arbitration for this reason. There is also a third possibility, called a joinder action, which may be commenced by the escrow agent if an agreement between the parties on release of the funds is not reached. You should consult an attorney to discuss the ramifications to your specific case of a joinder action.