At what BMI did you notice your body seemed leaner?

This is going to be hugely dependent on your ratio of fat mass to muscle mass...not so much BMI.

BMI is the worst thing to base your health on. Go off body fat % only. You don't even need to worry what the scale says if your are less than 18% body fat.

BMI has long been correlated in medical studies with heath factors "proving" statistically that the lower it is, the "healthier" you will be generally.

However, BMI is NOT well correlated to the low body fat and high LBM levels found among body builders or fitness advocates, because all it does is measure the ratio of weight vs height w/o regard to BF or LBM.

Using only my experience as an example, at 5'8" and my highest weight recently (196), my BMI was 29.8 rated at overweight and only a few #'s from obese w/a BF% well over 20%.

After a year of dieting and working out religiously, at 157-158# and only 10% BF (measured hydrostatically) now, my BMI is 24, just 1 point w/in the "normal" range and only 1 point from being classified as overweight, which would absolutely ridiculous to look at my stats and body.

There is no doubt that dropping my BMI from almost 30 to just under 25 from overweight & borderline obese to normal per BMI has improved my health - - most notably in my BP which now routinely measures around 110 over 70, which is considered ideal, from prehypertensive at 130-140 over 80-90 b4 - - it really says nothing about my fitness and physique.

For those things, I rely on my BF/LBM measurements using DXA & hydro, my endurance on my rower at home and the Stairmaster at the gym, my 1RM lifting #'s plus what I see standing in front of the mirror naked.

Using these measures, I did not begin to start "looking" lean until I got down to 14-16% BF and did not actually "become" lean until I hit 10%. So, OP, you should look to these measures (and not BMI) as indicators of your progress towards your goal of leanness.