Maybe try this....look at the taper of the leg before you cut it off. Then after it is cut, go up the leg an appropriate length and start a gentle taper in the side and inseam. My guess would be about the knee.... I think you will have to divide the taper between the two seams or the leg will be wonky....how's that for a sewing term. It is hard to define an amount of taper or length. Each pair of pants are different. You could baste the taper in and have him try the pants on to see if they fit ok before you sew.
Hope this makes sense, if not I will try again or maybe someone else will be able to better say it.
Murphy

Thanks, yes I understand what you mean. I have thought of that but sometimes the seams are not simple flat seams but those flat-felled seams and I'd have to do a lot of ripping and re-sewing. Or I could take them somewhere to get altered but then I'd pay more than the pants are worth. These are casual pants. I wish he wasn't so short!!!
Thanks again!

Do the pants taper that much? Is your husband that particular? Especially casual pants, I wouldn't agonize over an inch or two in circumference, really.

I have altered clothes for a living for thirty years, and we *don't* taper something to original opening just because it's hemmed. And I hem things for a lot of short people.

The exception is putting the original hems back on jeans. Obviously, the leg opening and the hem we're stitching back on have to measure the same.

I am a short woman, only 4' 10", so most pants I buy need to be shortened by 4 - 6". These pants that fit me well are generally tapered so shortening them is a real pain. My question is how I am to do this - fit the more narrow pant width into the larger some way, or the other way around? I hope there's sewing genius out there that can help. Please and thank you.

I always taper all the way to the crotch, and this way, you can replace the flat fell seams with simple seams. I finish the seam with a serger, and this make a good alternative to flat fell seams. If your serger is a four thread model, you can just use the serger to taper the legs.

After cutting the legs to length, I generally sew the inseam straight up for an inch or two to make it easier to hem the bottom of the leg. I make the taper start about 1-1/2 inches from the bottom of the leg. I do the same when I am making slacks.