i went from L6 IC to EM (skipped the senior EM title) at my last company. took the role because i wanted to try it, because someone asked and i wasn't doing anything else interesting at the time. classic mistake, honestly.
18 months later i wanted my technical identity back. the question was: what level would i come back as?
here's what i found. the answer is: it depends on how long you were managing and how honestly you assess your technical drift.
if you were EM for less than 2 years and you kept some technical involvement (architecture reviews, coding on nights for side projects, staying current on your stack), most companies will try to land you at the same level you left or one below. you'll need to pass the full coding loop again, which is jarring, but if your fundamentals are solid you can get through it.
if you were EM for 3+ years, plan for a one-level drop as a baseline and be grateful if you land at the same level. the market knows that people drift. a staff eng loop is hard even when you've never stopped coding.
what actually helped me: i was honest in screens. i said 'i've been managing for 18 months and my coding pace slowed, but i've been reviewing architecture and staying current on the domain.' honesty calibrates the loop better than pretending. i leaned hard on system design. that's where my EM experience actually helped: i had sat in the room where the big technical calls got made, and i could talk about tradeoffs at a level most ICs can't. i took 6 weeks to practice before applying. not kidding, i needed it.
came back at the same level i left. not everyone does. some people come back a level down and then promote quickly once they're in. that's also a valid path.
if you're thinking about the EM to IC switch: do it, if that's where your energy is. just prep for the loop.