A tolling agreement is an agreement to waive a right to claim that litigation should be dismissed due to the expiration of a statute of limitations. Its purpose is typically to allow a party additional time to assess and determine the legitimacy and viability of their claims and/or the amount of their damages without the necessity of filing an action. During this period, the parties waive any defense by way of any statute of limitations which would otherwise arise during such period.
Persons entering into a tolling agreement should verify whether it might void their liability insurance. The agreement should be worded so as not to resuscitate claims for which the limitations period has already passed and to be sure that the agreement only tolls the statute of limitations. The agreement should not contain an admission of wrongdoing, unless that is what you have agreed to.