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How to Get Your Pants to Fit Better at the Back Leg

While working at a menswear shop in the Atlanta area in the 1980s, I learned many techniques for altering ready-to-wear garments, including one for removing excess fabric from the back trouser legs. I continue to use this knowledge today when altering ladies’ clothing. If poorly fitting pants are an issue with your ready-to-wear or me-made clothing, consider this way to get your pants to fit at the back leg and below the seat.

Pin the excess fabric

In some cases, you can pinch out the excess along the back crease of the pants legs. If no crease is present,  just pinch out the desired amount below the seat at the center of the leg.

Pin placed vertically on back leg of women's gray menswear-look trousers
1. Place a pin vertically, as shown.
Close-up of pin in gray women's pants
2. Measure from the pin to the fold with a seam gauge or other device. Keep in mind that this amount needs to be doubled, as there is the same amount of fabric on the other side of that fold. In this example, the measurement is 1 inch total.
Seam gauge measuring from fold to pin on women's gray pants
3. Turn the pants inside out. Start to remove the stitches at the pants crotch seam, near the inseam intersection, making sure to give yourself enough room to do the alteration.
Stop removing stitches at the pants crotch seam
Release any serger stitches that keep the seams from spreading apart at the crotch near the inseam.
seam gauge measuring 1 inch from chalk mark to original inseam seamline on gray pants
Create a stopping point before you take too much of the seam apart, especially if the seam is sewn with a chainstitch.

Mark key points

4.  Now focus on the inseam. If you’re altering ready-to-wear trousers, you’ll see a notch farther down the leg, which indicates the knee level. Place a chalk mark there, as it will be the stopping point for the adjustment.

5. Remove the stitches at the inseam from the crotch to the notch at knee level.

At the back leg only, measure out from the original seamline at the crotch level, the amount you pinched out in step 2. Place a mark there; in this case, it is 1 inch.

seam gauge measuring 1 inch from chalk mark to original inseam seamline on gray pants

Continue to chalk-mark, following the curve of the original inseam, until you taper to nothing at the knee.


chalk-marked line along along inseam of ladies gray pants

Pin and stitch

6. Lay the pants’ front inseam seamline (indicated by a fold) on the chalk mark.

Starting at the knee, keep matching onto the line and pinning as you go until you reach the crotch level. You may find one seam is longer than the other. That is fine, as the excess can be removed later.

pinned inseam on ladies gray pants

pins secure inseam on altered pants leg

7. When the seam is completely pinned, sew along the pinned seamline. Start stitching at the crotch on one side of the pants, then stitch from the knee of the other side. This method of sewing one leg in one direction and the other in the opposite direction keeps the seam smooth—avoiding a pinch in the seam as you follow the curve. 

pinned pants inseam under a sewing machine presser foot

Remember to backstitch at the start and end of the new seams.

Pinned seamline of gray pants under the sewing machine presser foot

Stitch both legs before closing the seam at the crotch, and try the pants on to make sure you’ve removed the correct amount of fabric.

Completed stitching along inseam of gray pants

8. Once both sides are done, press the inseams open. Leave the excess fabric at the inseam, unless it is a large amount. In that case, trim the fabric with pinking shears, or cut it away with your serger.

Inseam of altered gray pants pressed open


9. Pin the pants crotch, with right sides together, and close the crotch seam on the original stitching lines. Remember to backstitch at the beginning and end.

Pants crotch seam of gray pants under a sewing machine presser foot

Stitch the pants crotch seam closed, backstitching at the beginning and the end

10. If the fabric at the crotch level extends too far, you can trim it away.

This alteration shortens the back crotch seam. If you are making the pants, you can adjust the pattern after you’ve determined the amount you need to remove.

The pants alteration is completed on the right leg only, below.

Get your pants to fit better by removing excess fabric from the back trouser leg, as shown on the right leg


There’s no need to remove excess fabric from a pants lining, as lining fabric has little give compared with fashion fabric. Removing the same amount of fabric from the lining would likely make the pants feel too tight. However, if you are removing a lot of excess from the fashion fabric, you would only need to remove about half the amount in lining. I learned my lesson.

I hope you’ll try this technique to get your pants to fit better. It has worked well for me.

For more on altering garments from Pamela Howard, click here.

Previous: How to Fix a Bulging Lap on Pants Next: Draft a Pants Sloper that Fits


  1. ozannie | | #1

    Sorry but I don't see any of the photos to which this article refers....

    1. ThreadsMagazineWeb | | #3

      Hi Annie, we apologize for the confusion. We had some technical difficulties and are rectifying them now. The full post will be made available soon - with pictures! Thank you for your understanding and patience! - Threads web team

  2. User avater
    sewsan | | #2

    Me neither - it would be much easier if they were included :-)

    1. ThreadsMagazineWeb | | #4

      Hi there, you're right and we apologize for the confusion! We had some technical difficulties and are rectifying them now. The full post will be made available soon - with pictures! Thank you for your understanding and patience! - Threads web team

  3. mkk5000 | | #5

    Thank you! This was very helpful!

  4. kimberlykra | | #6

    Thank you very much! I’ve often wondered how to eliminate the bagging at the back of pants. I can’t wait to try this weekend. I love seeing alteration tutorials, good ones are very hard to find.

  5. ozannie | | #7

    Thank you for adding the photos.
    As I see it, this alteration will decrease the back crotch length which may cause other problems.
    Definitely worth knowing though. Thank you.

  6. User avater
    pamhoward | | #8

    Hi OzAnnie,
    This alteration is very effective for those who need their pants adjusted due to excess fabric below the seat and at the upper thigh, and won’t necessarily cause additional problems. You may find it to be a technique that you can use along with other needed adjustments during your usual fitting process. Occasionally (but rarely), we would also need to do a side seam adjustment on customers who were very slim. Maybe I will do a post on that adjustment in the near future!
    Thanks so much,

  7. ozannie | | #9

    Thank you Pam. This technique is definitely something I will add to my toolbox. Still trying to achieve the "perfect fitting pants".

    Annette (OzAnnie)

  8. User avater
    Liza115 | | #10

    Brilliant! Thank you Pam. I always learn so much from you. Now that Bluprint is gone, I hope there is another way to see you "in action" so to speak. It would be great if Threads Online would take up the baton and offer full length classes from sewing professionals like you.

    1. User avater
      Silvercurls | | #15

      Craftsy is coming back!!

  9. delica | | #11

    Excellent article.

  10. User avater
    pamhoward | | #12

    Thanks so much to all of you for your kind comments :-)

  11. user-7047838 | | #13

    Pam - Thank you so much for this article. I recently had a client with two pairs of pants that needed this alteration, but I didn't know what to do, so she still has a baggy butt LOL. I will definitely use this information in the future.
    I love Threads, but don't find many articles that can help me with my alterations business. Keep it up!

  12. slilly92596 | | #14

    It would be great if Threads would add a print or pdf function to their site. I cannot get internet access in my sewing studio and to be able to do a print out to save or download a pdf to my tablet lets me be able to quickly reference these tips. Thanks

    This was a great tip and one I will use to tailor pants for myself and others.

    1. User avater
      Silvercurls | | #17

      I agree. I would love to print this article.

    2. User avater
      [email protected] | | #19

      I upload internet articles to my iPad. Upload to Books will convert to pdf .

    3. user-3766892 | | #20

      I just either get the pdf version of the article and print, or go wild and print the whole thing. If I’m on my iPad, I often send the article to my email address so I can open it on my laptop and either save it, or print. This saves space on the iPad.

  13. User avater
    Silvercurls | | #16

    Great article! Thank you!

  14. catstexas | | #18

    Wonderful clear explanation of how to fix this problem. Thanks Pam, keep writing.

  15. Deleted | | #21


  16. user-6880608 | | #22

    Love everything Pam shares! Her online courses were fabulous too!

  17. purejoy | | #23

    Thank you Pam. You were meticulous in your explainations, as always. If I may recommend this to others, Pam’s class on Craftsy teaching how to make a jacket/blazer is phenomenal. I watch the techniques over and over and have had great success.

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