A well-made coat can last for a great many years; however, you may want to have the coat altered as needed to keep it in fashion. You might also have found a beautiful coat second-hand or on sale that needs alterations in order to fit perfectly. If you are petite or tall, broad-shouldered or large-busted, having your coat altered can improve the fit substantially. A good tailor or seamstress can make the necessary changes to women's coats for a better fit, or restyle a coat for a more modern look.

Sleeve length is one of the most common alterations for women's coats. Petite women may need the sleeves shortened, and taller women may need them lengthened. Some sleeve alterations can be managed with only basic sewing and alteration skills, but a tailor or dry cleaner can handle this alteration at a very reasonable cost. If you do opt to alter your sleeves on your own, remove the stitching joining the sleeve hem to the lining. Bring the sleeve up as needed and hand stitch into place. If you are lengthening the sleeve, you may need to use a band of contrasting or closely matched fabric, as well as a narrow ribbon or trim to cover the prior hem fold.

If your coat is too long, bringing the hem up can improve the overall fit and line of the winter coat. You might also shorten an older coat to create a new, modern look. Open up the hemline, removing the stitching between the lining and the outer fabric. Measure your hem and carefully cut away the outer fabric, preserving a generous hem allowance. Fold the hem into place and press using a press cloth and steam iron. Cut away excess lining fabric and sew your hem into place by hand. The same method can be used to shorten a coat by just a few inches or more substantially.

More significant coat alterations can be a good choice if you have a dated but very good quality coat. You may want to talk to a tailor about the options available or try it on your own if you are willing to experiment. Narrowing side seams, nipping in a waist or even shaping the sides to create a fit and flared shape are all manageable alterations. Remove the lining completely before beginning your alterations. Try your coat on inside out and pin the changes you want into place. Stitch the alterations into place. Trace out a new lining pattern and alter the original lining or make a new one. Stitch the lining back into place.