Fuller Seat Adjustment for Trousers - Shore, Cove, Coastal

This is a simple and quick pattern modification that can be used to adjust pull-on style pants or shorts for a fuller seat.  Use your own measurements to customise the rise for your preference and comfort.  

This pattern modification works well for the Shore Pants, Cove Shorts, and the Coastal Shorts.  


  • Pattern pieces (we're using the Shore Pants)
  • Measuring tape
  • Scrap paper
  • Pencil
  • Ruler
  • Scissors


To determine how much length to add to the rise of your trousers, use the following method to measure rise:

  • Tie a ribbon around your waist at the height you would like the waistband to sit. 
  • Place the end of the tape measure on the ribbon at the centre front, thread it through the legs, and bring it up to the ribbon at the centre back, keeping the bottom of the crotch/rise seam at the position you want it to sit between your legs (allowing for ease). 
  • Pull the tape measure up to meet the ribbon at the back and note the measurement.  

Compare your own measurement to the your size on the Finished Garment Measurement Chart (in the pattern tutorial).  If the measurement on the chart is smaller than your body measurement, or doesn't provide enough ease for a comfortable fit, then add the difference to the pattern back rise.

For example, the size 50 Shore Pants have a rise of 31.9" (81cm).  Our sample sewist measures and finds that they need a rise of 35" (73.5cm) for a comfortable fit that brings the rise up to the desired position at the rear.  Calculate the difference between the two measurements to figure out how much to add:

Finished garment rise measurement 31.9" (81cm)
Sample sewist rise measurement 35" (89cm)
Difference = amount to add 3.1" (8cm)

Note that the amount of ease required will vary depending on personal preference as well as the intended fit of the trousers.    

Adjust the pattern pieces

1.  Cut through the lengthen/shorten line, stopping at the seam allowance on the side seam, leaving a bit of paper intact to create a pivot point 3/8" (1cm) from the pattern edge.  

Fuller Seat Adjustment for Trousers by Twig + Tale

2.  Pivot the front rise until it is lengthened the amount determined above.  In our example, this is 3.1" (8cm). 

Fuller Seat Adjustment for Trousers by Twig + Tale

3.  Place a piece of paper behind the pattern and tape it into place to secure the two pieces.  Blend the front rise so it is a smooth curve.  

Fuller Seat Adjustment for Trousers by Twig + Tale

Once your pattern piece is adjusted, continue to cut and sew as outlined in the tutorial.  We always recommend sewing a muslin to check the fit before cutting into your final fabric.  

Enjoy wearing trousers with a customised fit!

Read more T+T pattern adjustment tutorials here: