I'm not there yet, but I'd suggest finding out your body fat percent, since BMI is a bit of a faulty measurement. When we lose weight a lot of the lean mass can drop away (weights help, but cardio doesn't really), so it's hard to say whether you have a healthy body fat percent or not. It's possible you have low lean mass and higher fat despite your BMI, in which case, if you're not feeling like you look the way you want to, you might be able to solve it by doing squats and lifting some weights. It'll make you look thinner even while gaining a few pounds.
I personally think a body fat of about 25% (give or take 5%) will be where I draw the line... when my body fat is in a healthy range, and I feel good in my own skin. Those two things together.
You can find out your body fat via a pinch test at the gym (find someone experienced), or by DXA scan or underwater weighing. The gym way is probably the easiest and definitely the cheapest of those, and still pretty accurate (although it can underestimate body fat a bit, I read). The scales you can buy that use electrical impedance give results that fluctuate a lot based on hydration (muscles hold onto water), but might still be fine to give you a general picture of where you're at.
By the way congrats on your weight loss! You've done an amazing job so far, and I wish you all the best maintaining.
When do you call it?
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