Program Error vs Misunderstanding QCD calc

[Nature_Lover]

TT 2024 Mac; My RMD was 100000. I took out 100230 of which 18k was a QCD for a charitable annuity to a college. That should leave 82230 income on form 1040 line 4b no? but TT has 40122  there. What do I not understand?? I'd love to pay less but ?

Made up numbers multiplied by same factor based on made up 100k RMD 

[dmertz]

Do you have basis in nondeductible traditional IRA contributions?  Check to see if TurboTax has prepared Form 8606 Part I.