Seven to ten if you do laundry once a week. That covers a shirt a day with a couple spare for spills and gym days, and it means nothing sits in the drawer long enough to yellow.
If you do laundry every two weeks, double it. If you sweat through two shirts a day at work, double it again. The number is not really about shirts. It is about how long you go between washes.
The formula
Take the number of days between laundry loads. Multiply by how many shirts you go through in a day. Add two.
Laundry every seven days, one shirt a day, and you land at nine. That is why a 6-pack plus whatever you already own tends to be the right first order for most guys.
The plus two matters. It is your margin for a coffee spill on Tuesday and a shirt that is still damp on Thursday. Without it you end up wearing something you already wore.
Adjust for what you actually do
Working outside in Florida heat is not the same as sitting in an office. If you are changing shirts at lunch, your daily number is two, not one, and your total roughly doubles.
Undershirts count separately. If you wear a tee under a work shirt every day, that is its own rotation and it wears out faster because it takes all the sweat. Most men underbuy here and end up wearing thin, stretched undershirts for years.
Gym shirts are a third category. They get washed harder and more often, so they age fastest.
Why owning too few costs more
A shirt worn twice a week wears out in about half the time of one worn once a week. Same shirt, same wash cycle, double the mileage.
Running a rotation of five when you need nine means every shirt you own is doing nearly twice the work. You replace the whole set in a year instead of two.
Buying more shirts up front is cheaper over time, which is the whole argument for packs. At $4.75 a shirt, going from six to twelve costs less than one decent single tee.
Signs your number is too low
You wear the same shirt twice between washes. Laundry day is non-negotiable rather than flexible. You own a shirt you keep wearing even though the neck has gone loose, because the alternative is nothing clean.
Any of those and you are short.
A reasonable starting setup
Six plain tees in your main color for daily wear. Three or four in a second color for variety. A few tank tops if you layer in summer, and separate undershirts if you wear a uniform.
That is one or two packs, and it holds for a couple years. Browse the full range in XS through 6XL.
