The amount of time one must carry a SR-22 differs depending upon state laws, the reason you are required to hold this financial responsibility certificate, etc. Most states inform you how long you will need to hold the SR22 when you are first required to obtain it.
If you believe your time period is up, you should contact your Department of Motor Vehicles, or like state agency, to see if you may take the SR-22 off or not. The DMV should also be able to tell you how many years the SR-22 is require for various infractions so you will know how much longer you are required to carry the SR-22 if your time is not up yet.
If you are permitted to end carrying the SR-22 then you should notify your auto insurer. In many states there is a form, such as the SR-26, that the insurance company turns into the state when you terminate your SR22 with them.
To get a quote for car insurance with or without the SR22, follow this link.