Most menswear email programs treat the second purchase like the first one. New arrivals, a lifestyle photo, a "shop the drop" button, and a size chart sitting one click away like he's never bought from you before.
But he has. And if he kept the chinos past the return window, he told you something more valuable than any quiz answer: his size works. He doesn't need to be sold on your fit anymore. He needs you to stop making him re-solve a problem he already solved.
I wanted to know how true that actually is, so I pulled the order history for an apparel brand we work with that started in menswear. About 21 months of orders, 29,334 customers who bought a sized men's item (tops in XS to 2XL, bottoms by waist). Here's what came back.
The size sticks. The product doesn't.
I looked at every customer who placed a second men's order at least 30 days after their first, so we're past the return-and-exchange noise and looking at people who kept something.
- 76% of the sized items in that next order were in a size the customer had already bought.
- 86% of those items were a style he had never bought before.
- Only 9% were the same style in a new color. Another 5% were straight replacements, same style, same color.
That last number surprised me. My pitch for this post was "your size, other colors," and the data mostly says no. Guys do rebuy the hero pieces in new colors (the pleated chino, the slub tee and the five-pocket jean led that list by a wide margin), but that's the minority behavior.
What actually repeats is the size. He trusts that your medium is his medium, and he takes that trust to a shirt, a sweater, a jacket he's never tried. The fit is the relationship. The product is just what he's buying this time.
So the play isn't "show him the same thing in olive." It's "show him new things, and stop making him check whether they come in his size."
What a confirmed size looks like in Klaviyo
Here's how I'd build it.
1. Write the size to his profile, but only after it's earned. Off the Placed Order trigger, wait out your return window plus a few days (35 days for a 30-day policy is fine). Then check that no refund or exchange came through for that order. If it's clean, use an Update Profile Property step to save something like confirmed_top_size = M and confirmed_waist = 32. Tops and bottoms get separate properties. A guy can be a medium in shirts and still be figuring out his inseam.
Don't write the size at checkout. At checkout it's a guess. After the return window it's a fact.
2. Split your post-purchase and new-arrival content on it. Once someone has a confirmed size, the email changes:
- The headline talks about fit he already knows. "Same fit as the oxford you already own, new fabric" lands harder than "New for Fall."
- Size charts and fit-finder modules come out. He doesn't need them, and they quietly suggest he might be wrong.
- Lead with styles that are in stock in his size. A launch email for a shirt that's sold out in medium is a bad email for every medium on your list.
3. Give the hero pieces their own lane. That 9% who rebuy in a new color is small as a share, but it's concentrated in a handful of staples. For anyone who bought the chino or the core tee, a "your size, three colors you don't own" email is worth a slot. Just don't make it the whole program.
4. Use the confirmed size for restocks. "Back in stock in your size" beats "back in stock" every time, because it removes the click where he finds out it's actually still sold out in his.
The Q4 problem nobody talks about
Here's the part that changed how I think about the next 90 days.
I grouped customers by the month of their first men's purchase and checked how many came back for another men's order 30 to 180 days later.
December brought in the biggest wave of new men's buyers all year, about 5,400 of them, more than double a normal month. Only 4.8% came back. The months right around it, November on one side and January through March on the other, all landed around 8%. December was the clear low, and it wasn't close.
(One honest caveat: the earliest months in this data run higher partly because some of those "first" buyers had history before my data starts. That's why I'm comparing December to its neighbors, not to last spring.)
My read on why: a lot of those orders aren't him. They're his partner, his mom, his sister guessing at his size off a tag in the laundry. The customer record says "bought a medium crewneck sweater." The real story is someone else bought it, and maybe it fit.
That matters for two reasons.
First, a Q4 size is a guess, not a confirmation. If you write sizes to profiles from holiday orders without the waiting-period logic above, you'll fill your account with wrong data and send "in your size" emails to the wrong size.
Second, the person on your list might not be the man wearing the clothes. Hitting a gift buyer with "your size, new colors" in January is a miss. She needs a gift-giver lane next November, not a reorder flow.
How I'd set up Q4 differently
- Ask. A one-question post-purchase email or a quick order-status page prompt ("Was this for you or a gift?") does more for your data than any model. Save the answer as a profile property.
- Don't confirm sizes on suspected gifts. If the answer is "gift," skip the size write entirely. If you don't have the answer, require a second purchase in the same size before you treat it as confirmed.
- Give January's self-buyers the confirmed-size treatment fast. The guy who bought for himself in December and kept it is exactly who you want in a fit-led flow by February, when most of your list is going quiet.
- Tag gift buyers for next season. They're not a reorder audience. They're a gift-guide audience, and they're easy to find again in October.
The point
For a menswear brand, whether it's shirting, denim, chinos or knitwear, the hardest part of the first sale is fit. Once he's solved it, every email that makes him re-solve it is friction you created yourself.
Your list already knows his size. Most programs just never write it down, and the ones that do often write down the wrong one in December.
These numbers come from one brand, and each brand's customers differ. If you run menswear, your size-repeat rate could be higher or lower, and your gift share in Q4 could look nothing like this. But I'd bet the shape holds: size repeats more than product, and holiday sizes lie.
If you're building out a fashion program, we've written more about how we approach email marketing for fashion and accessories brands.
