Shirts are made to be worn...and when they're worn, they stretch out. Everything from carrying groceries to doing yoga can loosen up your shirt's fabric, especially when moisture and sweat come into the equation. Fortunately, the same shirts that are most susceptible to stretching (namely cotton and cotton-blend varieties) also return to form rather easily with a little free time and a lot of hot water. A word of caution, though: fixing a stretched out shirt neck or stretched out v neck isn't as simple as fixing a shirt that's just overall stretched out.
Things You'll Need
White distilled vinegar (optional)
Fixing Stretched Shirts: Stovetop Method
Fill a large pot with water and bring the water to a boil.
Remove the water from the heat. Use tongs to carefully submerge the shirt in the water. If you want to shrink the shirt by a full size, do this right after taking the water off the heat. Alternately, let the water cool for about 5 minutes (if you wish to shrink the shirt about a half size) or 10 minutes (if you want to shrink it by about a quarter size) before putting the shirt in. This method works for 100-percent cotton garments and for some types of wool.
Let the shirt soak for about 5 minutes or so. The longer it soaks, the more it shrinks. Drain the water from the pot after the shirt has soaked.
Allow the shirt to cool, then thoroughly hand-wring it. Spread the shirt out on a flat surface, being carefully not to pull on the fabric as you lay it out flat. Let the shirt air-dry. If the shirt still hasn't shrunk enough, repeat the process until you find the right fit.
Fixing Stretched Shirts: Machine Method
Wash your 100-percent cotton shirt or wool garment for one cycle on your washing machine's hottest temperature setting. The combination of moisture, heat and agitation can help stretched fabric fibers to shrink back to their original state.
Remove the shirt from the machine and place it in the dryer. Run a drying cycle on medium heat until the shirt is completely dry. Set the dryer to high heat, unless the shirt's label warns against it, for a more intense shrinking effect.
Repeat the washing and drying process until the shirt is snug enough to suit your needs. Typically the first washing produces the most shrinkage. Although you'll get diminishing returns, subsequent washings may still subtly shrink the shirt.
Add a cup of white vinegar to the washing machine to keep your shirt's color from fading and bleeding, especially if you have to wash the shirt multiple times to shrink it.
Typically, top-load washing machines are more effective at shrinking stretched clothes, as they produce more agitation than front-loaders. More agitation leads to more fiber reversion, or shrinkage.
Preshrunk fabrics are less susceptible to shrinking by boiling or laundering; some may shrink slightly and others not at all. Fabric with a loose weave is more likely to shrink than tightly-woven textiles.
Always read and follow any instructions or warnings provided by your shirt's manufacturer. Shrinking results vary based on the material and brand of the shirt.
These methods might make a difference in the appearance of a stretched shirt, but won't necessarily fix a stretched out v neck or other stretched out shirt neck.