Old Navy and Sézane Both Launched Occasion Lines, So I Put Them to the Test

I love dressing up. While my job often requires me to go above and beyond jeans and a button-down, my personal style also leans more formal. Confession: I do not own sweatpants. More often than not, I’m wearing trousers when it’s cold and a dress when it’s warm. I love a white button-down and big, flowing skirt. I only wear sneakers on the penalty of death. Which really goes to say—life’s a party and I’m trying to dress for it. Recently, I noticed that Old Navy and Sézane—two brands you’d feel are polar opposites—launched formal wear with a handful of pieces that seemed oddly similar. I did what any good fashion editor would and took everything for a test run. After about six weeks of prancing through parties, here are my honest thoughts about each, and which one I’d choose to dress me for my next night at the ballet.

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Earlier this season, both brands launched formal wear collections: THE OCCASION by Old Navy and The Occasion Collection by Sézane. Both are more elevated takes on the brands’ offerings, meant to be worn for, well, occasions with a cocktail attire dress code or something akin to Royal Ascot. A piece or two from each might pass for black tie, depending on how formally adherent your fellow guests will be. 

I pulled four pieces from each brand—much of which resembled the other—and wore them to various events over the course of six weeks. That included a Broadway play (John Proctor Is the Villain was great, BTW), summer book launch and nights out with friends. Factors I considered were material, comfort, aesthetic, versatility and sustainability.

Old Navy is definitely the more affordable option—Sézane’s most expensive piece is about ten times the cost of one of Old Navy’s full-priced items. But when it comes to materials, Sézane has the upper hand. The brand prioritizes more natural fibers, like linen and silk, over synthetics like the recycled polyester that comprises the entire Old Navy collection.

Zac Posen did a great job injecting fun and whimsy into the Old Navy collection, while still making it feel accessible to a range of ages and sizes who might shop there. I could see my mom, who is in her 50s, wearing clothing from the line as easily as I, someone in her 20s, did. On the other hand, Sézane isn’t very size inclusive. The designs are also most appealing to women in the 20s and 30s—many designs require that you forgo a bra and aren’t as stretchy. One plus I did appreciate, however, is that Sézane includes suits in their collection.

Old Navy is more budget friendly and versatile across ages and sizes. Sézane will give you the French-girl flair and better-quality textiles. Personally, I found a lot to love with both, and will be floating in the Sophie skirt and the Zac Posen polka dot two-piece all summer long.