Severance and unemployment, do they overlap? (Spokane)

My employer is paying severance in instalments and I am not sure whether to file now. There are 14 people counting on me, so I am trying to be careful. I also wonder about the job-search requirement. How did your state treat it?

Keep everything in writing and save the confirmation numbers. It saved me later.

Some states only count certain kinds of severance. A local workforce centre could tell me which.