To adjust armhole depth on a sewing pattern, first identify why the armhole feels tight or gapes, then correct the part of the bodice responsible—such as the armscye depth, armhole curve, horizontal ease, shoulder slope, or dart shaping. The right adjustment depends on where and how the fit problem appears.
In this guide, you’ll learn how to assess tight and gaping armholes, what can cause each problem, and how to make supported bodice pattern adjustments before sewing your finished garment. These fitting principles can also be useful when working with Winslet's sewing patterns and checking whether a bodice needs personal fit adjustments before cutting your final fabric.
What Is Armhole Depth on a Sewing Pattern?
Armhole depth relates to how the armhole sits vertically on the body, particularly around the underarm. If the armscye is too short, the armhole may sit too close to the armpit. If it is too long, the lower armhole can contribute to gaping.
However, armhole fit is not controlled by depth alone. The shape of the armhole curve and the amount of horizontal ease can also affect how the area fits.
This means that an armhole that feels too tight should not automatically be lowered, and an armhole that gapes should not automatically be raised. First, identify the likely cause of the problem.
Why Is My Armhole Too Tight?
A tight armhole can result from an armscye that is too short, armhole curves that are too shallow, or insufficient ease in the horizontal measurement.
Possible causes include:
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An armscye measurement that is too short
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Armhole curves that are too shallow
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Insufficient ease in the horizontal measurement
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Not allowing enough ease when working from the upper-bust measurement
A useful fitting clue is an armhole that rides very close to the armpit. Even if the sleeveless bodice is wearable, consider how the same area may feel once a sleeve is attached.
Before changing the pattern, determine whether the problem comes from armhole depth, curve shape, or ease.
How Do You Fix a Tight Armhole?
A tight armhole can be corrected by lowering the armscye when the vertical measurement is too short or by deepening the armhole curve when the curve itself is too shallow. Which adjustment you choose should be based on the cause of the tightness.
Option 1: Check the Armscye Measurement
If the armhole sits too high under the arm, reassess the armscye measurement before altering the curve.
In the fitting example used here, two measurements produced different results: 8½ inches and 8 inches. Rather than immediately choosing one, a better approach would have been to use the midpoint of 8¼ inches.
This highlights an important fitting principle: if repeated measurements differ slightly, consider the difference carefully rather than automatically choosing the smaller measurement.
Option 2: Deepen a Shallow Armhole Curve
If the armhole depth is suitable but the curve is too shallow, reshaping the curve can create a deeper armscye without making a separate vertical depth adjustment.
How to Deepen the Armhole Curve
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Examine the existing armhole curve.
Check whether the front or back curve appears too shallow for the fit you need. -
Determine whether the armscye itself needs lowering.
Do not automatically change both depth and curve. Decide which area is causing the problem. -
Redraw the armhole with a deeper curve.
Bring the curve farther inward where additional shaping is required. -
Check the front and back separately.
The front and back armhole curves do not necessarily require identical shaping. -
Check the side seams.
Make sure the corresponding side seams still match after altering the armhole. -
Review the finished curve.
Check that the transition into the surrounding pattern lines looks appropriate. -
Reassess the fit.
The altered armhole should feel better around the underarm without creating a curve that is unnecessarily deep.
When shaping curves during bodice drafting, one method is to square inward slightly before beginning the curve. The measurements used in this method are 3/8 inch at the front armhole and 1/4 inch at the back armhole. This can help avoid curves that are too shallow.
These are drafting references from this particular method rather than measurements that every existing sewing pattern must be altered by.
Can Making an Armhole Too Deep Cause Problems?
Yes. An armhole that is made too deep can affect comfort and sleeve mobility.
It can be tempting to keep lowering or deepening an armhole when trying to eliminate tightness, but more depth is not always better. If the armhole becomes too deep, a sleeved garment may feel uncomfortable and restrict the way the sleeve moves.
The goal is therefore not to create the deepest possible armhole. It is to create an armhole that provides the necessary room while still working correctly with the rest of the bodice and sleeve.
If you'd like to see these armhole fitting issues and bodice adjustments demonstrated visually, you can watch the video below.
Why Does an Armhole Gape?
A gaping armhole can have several causes, and the location of the excess fabric can help identify which one is responsible.
Possible causes include:
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A back dart may be needed when the gaping occurs at the back.
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The shoulder slope may be too high when the gaping appears closer to the shoulder.
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The armscye may be too long when excess appears around the lower armhole.
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There may be too much horizontal ease when the gaping appears closer to the lower armhole curve.
Because these problems have different causes, the location of the gaping is important. Do not remove fabric from the armhole without first checking where the excess appears.
How Do You Fix a Gaping Armhole?
When excess fabric is concentrated around the armhole curve, you can measure the amount of gaping on the bodice and transfer that excess into an existing dart. This removes the unwanted fullness from the armhole while redistributing it elsewhere in the bodice.
How to Transfer Armhole Gaping Into a Dart
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Put on the bodice.
Assess the armhole while the bodice is on your body so you can see where the excess appears. -
Pinch out the gaping.
At the area that stands away from the body, pinch out the amount of excess needed to make the armhole sit correctly. -
Mark the excess.
Mark the amount you have pinched out. -
Measure the adjustment.
Measure the excess so you can reproduce the same amount on the bodice pattern. -
Transfer the measurement to the pattern.
Mark the measured amount at the corresponding area of the armhole. -
Move the excess into a dart.
Transfer the unwanted armhole fullness into an existing dart. On a bodice block containing both a bust dart and waist dart, the excess can be moved into the bust dart. -
Redraw the altered pattern.
Complete the pattern adjustment so the armhole reflects the removed excess and the dart incorporates the transferred amount.
Where the excess is transferred can depend on the bodice and its existing dart structure. The important point is that the gaping is measured first rather than removed by guesswork.
How Do You Know Which Armhole Adjustment to Make?
The location and type of fit problem are the best clues. Start by observing the bodice on the body rather than changing the pattern simply because the armhole does not look right on paper.
A practical way to diagnose the problem is:
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Armhole riding close to the armpit: Check the armscye depth and whether the curves are too shallow.
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Generally tight through the armhole area: Check whether there is enough horizontal ease.
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Gaping at the back: Consider whether a back dart is needed.
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Gaping near the shoulder: Check the shoulder slope.
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Gaping near the lower armhole curve: Check whether the armscye is too long or there is too much horizontal ease.
This diagnostic step matters because two armholes can show different fitting problems even when both initially appear to need a simple depth adjustment.
Why Does Horizontal Ease Matter Around the Armhole?
Horizontal ease affects how much room the bodice has around the upper body, so insufficient or excessive ease can show up as an armhole problem.
This is particularly worth considering when drafting from an upper-bust measurement. A circumference measurement does not necessarily account for how the front of the body projects and slopes, so some additional ease may be needed.
In the drafting approach described here, an additional 1/8 inch of ease is added to the measurement when working from the upper bust.
This does not mean every armhole problem should be corrected by adding ease. Instead, horizontal ease should be considered alongside armscye depth and armhole shape when diagnosing the fit.
Common Armhole Adjustment Mistakes
The most important mistakes to avoid are correcting the wrong fitting problem, making the armhole unnecessarily deep, and losing accuracy when redrawing the pattern.
Assuming Every Tight Armhole Needs a Deeper Curve
A tight armhole may result from a short armscye or insufficient horizontal ease rather than the curve itself. Diagnose the cause before redrawing.
Making the Armhole Too Deep
More depth can create its own fitting problem. An excessively deep armhole may affect sleeve comfort and mobility.
Ignoring Where Gaping Occurs
Gaping near the back, shoulder, and lower armhole can have different causes. Use the location of the excess fabric to guide your adjustment.
Forgetting to Check the Side Seams
After changing the armhole curve, check that the corresponding side seams still match.
Repeatedly Outlining a Pattern
Repeatedly outlining an existing pattern piece rather than accurately tracing over it can introduce changes to the pattern. Be mindful of maintaining the original pattern dimensions when transferring or redrawing pieces.
Getting a Better Armhole Fit
A successful armhole adjustment starts with identifying the actual source of the fitting problem. If the armhole feels tight, check the armscye depth, curve shape, and horizontal ease; if it gapes, use the location of the excess to determine whether the issue relates to the back, shoulder, armscye length, or ease.
Make one adjustment based on the fitting evidence rather than automatically lowering, raising, or reshaping the armhole. When you're ready to apply your fitting skills to another project, explore Winslet's sewing patterns collections for your next sew.
FAQs
How do I know if my armhole is too high?
An armhole that rides too close to the armpit can indicate that the armscye is too short. However, shallow armhole curves or insufficient horizontal ease can also contribute to tightness, so check these factors before making an adjustment.
Should I lower the armhole if it feels tight?
Not automatically. First determine whether the armscye is too short, the curve is too shallow, or the bodice lacks sufficient horizontal ease. Lowering the armhole when depth is not the problem can make it unnecessarily deep.
Why is my armhole gaping at the bottom?
Gaping closer to the lower armhole curve can indicate that the armscye is too long or that there is too much horizontal ease. The excess can be measured on the bodice before deciding how to alter the pattern.
Can I move armhole gaping into a bust dart?
Yes. On a bodice with a bust dart, excess pinched out at the armhole can be measured and transferred into the bust dart. The dart then absorbs the excess that was previously creating the gape.
Does armhole depth affect sleeves?
Yes. Armhole shaping and depth affect how the sleeve works with the bodice. An armhole that is too deep can contribute to uncomfortable sleeve movement, while an armhole sitting too close to the armpit may also become more noticeable once the sleeve is attached.
