No, Travelers does not have a grace period unless required by state law. In states that don't have a mandatory grace period, Travelers may cancel a policy as soon as a payment is missed. But if there is a mandatory grace period, policyholders can pay their past-due premium within a certain timeframe in order to avoid a lapse in coverage. If the grace period ends without the necessary payment being made, Travelers will cancel the policy. If you are able to pay the bill before your policy is canceled, Travelers will charge you a late fee, though the exact amount depends on your state.
When you miss a car insurance payment, Travelers will usually send you a notice of cancellation that includes the final date that they will accept payment before your coverage lapses. Since almost every state requires you to have car insurance, a lapse in coverage could lead to serious consequences, including fines and even a license suspension if you're caught driving. Additionally, going without insurance designates you as a high-risk driver and can make car insurance more expensive in the future, so it's important that you pay your car insurance premium prior to the final cancellation date.