I am a sober for 2 1/2 years. I have a past felony record and looking for employment in the riverside ca area. How far back do pre employment background checks go.

I hear you and know that this difficult but it all depends on what kind of facility you are looking for employment in. Can you tell us a little more about what you are trained for. If it is healthcare then I would forget it.

Background checks cost more the further back they go, and each employer makes their own decisions about what they want to pay for.
I think the SHORTEST number of years is 7.

The question is moot, really. Each job application is going to be different. Many employers use a standard form that asks if you have been convicted of a felony in the last 5 years. Even if they ask verbally, there's no point in lying. It's a waste of your time and theirs. And you could instead prepare a good little speech about your last 2 1/2 years, which sounds pretty good to me.

Some places may not even check references. Others may only wish to check a few years. For many they will go back 10 years or more.