3XL+, 4XL, and 5XL
We're working on them now
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Development, Testing, Production
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New!
January 2026
We're working on more fits
Fits for:
3XL+, 4XL, and 5XL
and sizes in between
3 FIT Theory - Package Icon
 
Limited Release!
Black Crew Neck Fittings
Then, limited colors and styles are available, after your Fitting. And, we're actively working on more colors, styles, and fabrics now.
Get Fitted Now
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  • Nothing to join.
  • No yearly fees.
  • Not a subscription.
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  Free Shipping
Arrives in a few business days, including Saturdays.
Prepaid Return Icon
  Return Mailer Included
Prepaid Return Mailer Included. No hassle. Nothing to print.
Here's how it works:
  • We send you 3 different fitting shirts, not just sizes.
  • Try them out! Wash 'em! Wear 'em!
  • Pick your fits.
You'll then receive discounted Preferred Pricing on all future orders of additional shirts. (More on that later, further down this page)
Try 3, Return 2, Keep 1
3 FIT Theory - Package Icon
Get Fitted Now
Includes 1 Shirt Free
49
Regular Price
29
Limited-Time Only
Our Timeline
Development, Testing, Production
January 2026
Update
We're in Production now!
The feedback has been overwhelemingly positive.
We've implemented feedback, made adjustments, and are in Production now.
Get Fitted Now
You can order the Fitting now, and receive discounted Preferred Pricing towards future orders once your pick your fits.
Preferred Pricing Icon
Preferred Pricing
On All Future Orders
Up to
30% Off
After your fitting
Additional shirts will start at:
27
Regular Price
19
Your Price
United States Addresses Only & Subject to Terms ▸
Brad Pitt once asked,
“What's in the box?”
49
Regular Price
29
Limited-Time Only
The Fitting:
1-time fee. The Fitting is not a subscription.
3 FIT Theory - 3 different shirt fits icon
We send you 3 different shirts.
3 completely different fits, not just "sizes"
3 FIT THEORY - Keep 1, Send 2 Back Icon
Keep 1. That's your fit.
One shirt is included free with your fitting.
3 FIT THEORY - Prepaid Return Mailer Icon
Send back "the other 2" shirts,
Using the prepaid return mailer. Nothing to print.
That Completes Your Fitting.
Note: You are not charged for “the other 2” shirts upfront. We just trust you to do the right thing, so don't order if you're an a**hole :)
3 FIT THEORY LOGO
Your Fitting
What “Size” Do You Typically Wear?
We use this as the starting point to find your fit.
Note: Our Shirts Don't Shrink.
“Tall Size” Info ▸
Length?
Note: only “Standard” and “Tall” for now. Will eventually make “Less” versions, too.
Crew Necks
All 3 shirts will be different fits in the neck you choose.
Which Color?
This is just for your fitting. All colors will be unlocked and available to you after your fitting, regardless of what you choose now.
Fabric
We use our “Shake & Bake” Fabric for your fitting. All Fabrics are available to you after your fitting.
Shake & Bake
50/50 Cotton/Poly - 145gsm (4.3oz)
“Equal parts awesome & goes great with everything. A truly versatile fabric and great for all-day wear.”
Fabric Singles
30 Singles
Fabric Weight Icon
145gsm / 4.3oz
Fabric Blend
50/50 Cotton/Poly
About
This is the fabric we use for fittings. Why? It's universally loved and good for almost everything: gym shirt, undershirt, and everyday wear. It's an equal parts blend of 2 different fabrics and great for its versatility, quicker drying, and a bit of moisture-wicking built in. It's soft, yet durable, and great for all body types.
Any Additional Comments?
Optional. Not required.  
Click To Add Comment ▾
Your Fitting.
Note: This is a 1-time charge. This is not a monthly subscription.
The Fitting includes free shipping to you.
The Fitting is a 1-time charge, not a monthly subscription.
What if you don't like any of the shirts? Returns Policy ▾
You can refit for $6 to $10 (depending on your Fitting).
Or, receive a refund of your entire purchase amount less $10.
Full Shipping & Returns Poly here
Limited-Time Only
20
Off Your Fitting
Discount Applied
See Below
Order Summary
49.99
1-Time Charge
Not A Subscription
3.00
V-Neck
Included
Crew Neck
20.00
Deluxe Fitting
Try 3, Keep 3, Get $30
Included
Basic Fitting
Try 3, Return 2, Keep 1
- $20.00
Discount
29.99
Total
Pay With:
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UNITED STATES
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Got Questions?
3 FIT Theory - Got Questions Icon More Info 3 FIT Theory Logo F.A.Q Size Help Icon Size Chart