Plus-Size Turtleneck and Mock Neck Dresses: Test the Collar First
I'd rank turtleneck dresses by the collar, not the silhouette. Everything else about a knit bodycon is easy to predict from a photo. The collar is the part that sits against your neck for eight hours, and it either disappears or becomes all you notice.
Here are four high-neck dresses from DressMePlus, grouped by how they handle it. I'm going from the listings and photos, and I haven't worn any of them.
Turtleneck, mock neck, and why the difference matters at your throat
A true turtleneck, which Wikipedia also calls a polo neck, has a close collar that folds over and covers the neck. The mock version looks similar and stands up in the same way, but the tube that forms the collar is sewn flat to the neckline instead of folding. Wikipedia notes that it clings smoothly and works well with a zip.
In practice that gives you two different tests. A folded collar adds a double layer right at the throat, so check it for bulk. A stand-up collar is a single layer, so check it for tightness. If you have ever pulled at a neckline in a mirror, you already know which one bothers you.
Before you buy any of these, pull a tape measure loosely around the base of your neck and compare it with the neck opening if the listing gives one. If it doesn't, assume a pullover knit has to stretch over your head and back down again, and read that as a reason to pick fabric with real give.
Two midis: one with sleeves, one without
The Turtleneck Ribbed Rayon Long Sleeve Bodycon Midi Bandage Dress is the quieter of the two, and it's the one I'd pick for a long day. The photo shows a single-layer stand-up collar, a fine vertical rib, long fitted sleeves and a hem around mid-calf. The interest is at the waist, where wide flat bands cross over the ribbing. A band at the waist is a sizing question more than a style one: a bandage wrap sculpts only if its length lands where your waist actually is, so compare the listing's waist and torso measurements before the colour.
The Turtleneck Sleeveless Split Plus Size Bodycon Midi Dress goes the other way. In the photo the knit looks thick and structured, the mock neck is short, the armholes are cut close and there is a small split near the hem. Sleeveless plus a high neck means the arm opening does the work that sleeves would, so check the bicep and armhole numbers. It also layers well under a coat or an open cardigan, which the long-sleeve one will fight.
If I had to choose a single piece of the two for a cold office, it would be the sleeved one. For a dinner where you'll spend most of the evening in a coat, the sleeveless one is less bulky.
Two dresses where the high neck is only half the story
The High Neck Long Sleeve Bodycon Mini Dress is the plain one. The photo shows a smooth stretch knit with a faint sheen, a high neck that covers the throat, long sleeves to the wrist and a hem at mid-thigh. The listing describes it as a pullover. There's nothing to fuss with here, which is the appeal, but a mini in a bodycon cut is a length decision. If you're tall, or you sit a lot, hold the hem measurement against your thigh before you commit.
The Velvet High Neck Hollow Out Long Sleeve Bodycon Maxi Dress is the opposite of plain, and it surprised me. The collar closes at the top with a decorative knot button, then drops straight into a deep plunge that runs most of the way down the bodice. The photo also shows a zip along the front and a high slit when the zip is partly open. It's a high neck in name only. If you chose a turtleneck for coverage, this isn't the dress.
Velvet is also the fabric where a close fit shows the most. It records every seam and every wrinkle across a lap, so a dress this fitted deserves a trial run sitting down at home first. I'd wear it to an evening event and nowhere that expects a conservative neckline.
