Length of time one needs to maintain SR-22 depends on various factors including state specific law and the reason for which you are required by the state to maintain the SR-22.
Although laws pertaining to SR-22 vary by state, in most cases the minimum duration one needs to maintain SR-22 is at least three years. As long as you pay the insurance premium in a timely manner the certificate remains valid. If you fail to pay the premium or let your insurance coverage lapse for any reason, your insurance company will notify this to the state. State may suspend your driver’s license and may require you to maintain SR-22 for a longer period of time in order to reinstate your driver’s license.
If you need an SR-22, it's important to know when the clock starts ticking - the period of time you are required to hold the certificate might begin on the day your license was suspended or in some states, it may not begin until the date you are eligible to reinstate your license. Please refer to your state DMVs website for more accurate information.
It is required to show continuous SR-22 insurance coverage for at least three years (more in some states). In case of lapse of expiry of your policy, the insurance company is mandated to notify the state. Not following the terms of your SR-22 policy has serious repercussions, and may result in suspension of your license. Once the time requirement of your state is rightly fulfilled, your SR-22 status is usually lifted. For filling an SR-22, it is prudent to contact your insurer to obtain the documents for submission to your state department.