Old Navy wants to serve all customers regardless of size. As the retail chain prepares to be spun off from parent company Gap (NYSE:GPS), it has added its online Plus collection to 75 stores, according to a press release.

The about-to-be-independent chain now lets customers order from its Plus line from any store for home delivery with free shipping. Perhaps most importantly, the retailer has decided to offer each item at the same price no matter what its size. In most cases, clothing chains have charged more for larger sizes.

"Here at Old Navy, we believe in the democracy of style. Fashion is personal, and your clothing should make you feel confident," said Old Navy CEO Sonia Syngal in the press release.

Four women dressed in Old Navy clothes

Old Navy has added Plus sizes to 75 of its stores. Image source: Old Navy.

Why this makes sense for Old Navy

As it spins off from Gap, Old Navy has released plans to grow from 1,140 locations to about 2,000. That's a major leap, and extending its possible customer base makes sense for a chain looking to nearly double in size. The company explained its new size offerings in the press release:

Old Navy's women's line is offered in 74 different sizes and 8 different lengths, spanning sizes 0-30, XS-XXL, 1x-4x in Regular, Petite, Tall, Short & Long. In addition to the women's specialty lines of Plus and Petite, the brand also offers men's Big and Tall; boys Husky and Slim; and girls Plus and Slim.

Offering all sizes at the same price is perhaps the boldest part of this offering. A bigger shirt or pair of pants uses more material than a smaller one. In theory, that justifies charging higher for the bigger items, but it can be off-putting for customers purchasing the larger sizes.

Offering one price across each item regardless of size makes sense. The smaller sizes may cost a little more than they did before, but the change will likely not be noticeable. This is an inclusive move by the chain that's likely the start of bringing its full range of sizes to a larger range of its stores.

This is a smart play

Old Navy can use these 75 stores carrying its Plus line as a sort of lab. It can learn which items sell, and determine how to bring a broader assortment of sizes to the entire chain. The company has branded this initiative as Size "YES!" -- as in, no matter what your size is, yes, the retailer has it.

"That's why we launched Size 'YES!' this year -- because everyone deserves great style in their size whenever, wherever, however they want it," Syngal said.

That's not actually true yet; offering an expanded selection of sizes in 75 stores doesn't quite live up to Syngal's "whenever, wherever, however" comment. But it's a start, and the right business play, as it makes the chain a good option for a much larger customer base.

Serving more customers should allow Old Navy to expand its business. Larger shoppers are an underserved market, and they should appreciate having another place to shop where they can try things on in stores. The one-price model should also drive sales by making every customer feel equal.