Plastic notes phased in through the 90’s over about 5-10 years starting with $5 and $10, going up. I’m not sure the exact year we started going plastic, but it was around then. I don’t think we were up to the plastic $20 yet in 1993.
Paper notes were still pretty common in 1997. I remember finding them annoying because I had to separate them when doing the cash taking for work and the bank didn’t like getting paper and plastic notes bundled together.
Oops, I meant to reply to this comment but missed and made a top level reply instead.