I "let IRS calculate it" if it's under $100, because they never do.  This criterion may be higher, but it's a secret in the Law Enforcement Manual. (It may have been raised during Covid, but then lowered again.)  If it's over $100, I'll include it with the return unless the client tells me they would rather receive a bill and pay it in July.  

I had one client this year whose penalty would be $103 if tax with return was paid April 18.  So I encouraged her to file a couple weeks earlier, to keep it under $100 and therefore eliminate it.   It was really difficult to explain to her why that was important, and it wasn't when I had time to go into detailed explanations.