Top pick
This versatile zip plus Velcro swaddle can be used in many different ways and has a roomy style for easy diaper changes.
The Halo SleepSack Swaddle has two basic parts — a sack with armholes that zips and two outside wings that attach via Velcro around the baby’s arms or torso. When wrapped around the baby’s arms, it restricts their startle reflex — which can wake them up in the night — and makes them feel secure. The wings can be adjusted to make the part around the baby’s midsection as tight as needed, while a loose leg pouch ensures that the baby’s hips aren’t too constrained.
It can swaddle in several ways. Babies can sleep with their entire arms tightly tucked under the wings, with their hands up near their face and their arms wrapped up, or with one or both arms free of the wings. These options, combined with a long leg pouch, increase the chances that a baby will fit in this swaddle for at least a few months.
Instructions are featured on the swaddle itself. Words and pictures on how to swaddle in various positions are helpfully displayed on a label on the inside of a wing — a blessing for nervous new parents.
It can fit many sizes of babies. The newborn-size SleepSack Swaddle works for babies from 6 to 12 pounds, meaning the majority of babies will be able to use this swaddle from birth. And it features a long leg pouch that should accommodate taller babies. Halo also has a preemie size for newborns who weigh less than 6 pounds and a small size for babies between 13 and 18 pounds.
It’s available in several TOG weights and materials. The SleepSack Swaddle comes in TOG ratings (TOG stands for thermal overall grade, a measure of thermal insulation) of 1.5, 2.0, and 3.0, which correspond with bedroom temperatures ranging from 72 degrees Fahrenheit to 61 °F. And it’s available in different fabrics, including cotton, bamboo, and microfleece; we tested the 100% cotton. We also tested the Ideal Temp version, made of polyester rayon, which is supposed to “regulate” the baby’s body temperature, but we didn’t notice clear differences in our babies’ comfort levels between the cotton and the Ideal Temp versions.
Flaws but not dealbreakers
The fasteners are loud. It could wake up a drowsy or sleeping baby if you have to open or adjust the wings.
It can be difficult to get a very tight wrap around the arms. To get a super-snug fit, you may have to slightly lift your infant up so that the wing can wrap around the baby’s back. Some reviewers have said that their determined babies could wiggle their arms out of a not-tight-enough wrap.
Halo’s zipper situation is complicated. According to the company, all newer SleepSack Swaddles have two zippers (one that zips from the top down and one that zips from the bottom up), which is a feature that makes it much easier to quickly zip a baby into the swaddle and provides easy access to change a diaper without removing the whole thing. But the company is still selling one-zipper models as it works through old inventory; while they’re less common it’s hard to say which one you’ll get. In our 2025 home testing, the 100% cotton models we received were single zip, while the Ideal Temp swaddles were double zip. But we would have made the SleepSack Swaddle our top pick even if every model had only one zipper.
Key specs
Sizes: preemie (through 5 pounds), newborn (0–3 months; 6 to 12 pounds), small (3–6 months; 13 to 18 pounds)
Materials: available in 100% cotton, 100% bamboo viscose, polyester rayon, polyester, 100% organic cotton, velboa
