Pillows for the way you actually sleep
The pillow finishes the spine the mattress started. Rest and Keel are different tools, and the old pillow can sabotage a new bed.
By Thaw Sleep Team · May 7, 2026 · Updated September 12, 2026 · 4 min read

People replace a mattress and keep the pillow that shaped itself to the old sag. Then they write to us about the mattress. The pillow is doing a job the mattress cannot: holding the head so the neck isn't a hinge.
Height is the whole game
Side sleeping needs enough height to fill the gap from the shoulder to the neck. Too low and the head tilts down. Too high and the shoulder shrugs. The gap depends on shoulder width and on how far the mattress let the shoulder sink. A new, slightly softer bed often means a slightly shorter pillow than the one you used on a hard bed. That's why keeping the old pillow "for now" ruins the test.
Back sleeping needs less height. The head should not be pushed forward. If your chin is heading toward your chest, take fill out or change pillows.
Stomach sleeping needs the least. A fat pillow cranks the neck while your hips are already in trouble. Some people sleep with none. Keel is the wrong shape for that. It's a contour, built as a groove for a side sleeper.
Rest and Keel, without a fake ranking
Rest is the adjustable one. You can open it and add or remove fill. We'd pick it when you don't know your number yet, or when two people want different heights and you're buying two. The fiddliness is the point. A pillow you can't edit is a pillow you endure.
Keel is the shaped one. The groove holds the neck in a place, which side sleepers either love on night one or find bossy. If you move around a lot, a fixed shape can be in the way at 3am. Try it inside the 30-night window for pillows. That's shorter than the mattress trial on purpose. A pillow is easier to judge and easier to keep using past the point of honesty.
Neither pillow is a medical device. We don't claim they treat neck pain. If your neck pain is new or it runs down an arm, see someone qualified. A fill adjustment is not that appointment.
How to test them on a mattress trial
One change at a time if you can. New mattress, old pillow, for a few nights, if the old pillow wasn't already a problem. Then adjust. If you change both on night one, you will blame the wrong object. The mattress trial is 100 nights. The pillow's is 30, and only if it can be resold in hygienic condition. Don't take it on a trip and then expect a return.
Cases and washing
Use a case. Wash the case. The pillow itself has a care label. Follow that rather than a blog's guess about the dryer. A protector on the mattress doesn't protect the pillow. Sweat still happens.
A ten-minute fitting
Stand the pillow in the gap. On your side, the gap is from the mattress to your neck, shoulder included. If the pillow is taller than that gap before you compress it, it's too tall unless it compresses a lot, and most don't compress as much as people hope. On your back, look at the ceiling. If your eyes are aimed at the wall behind the headboard, the pillow is pushing you forward. Take fill out of Rest until the aim is more or less upward.
Do this on the mattress you intend to keep. A pillow fitted on the old sag will be wrong on the new flat bed. That's the most common "the mattress gave me a neck ache" letter, and the mattress didn't.
Wash the case before first use if you like things that way. Let the pillow air out of the bag. Don't judge the smell of a sealed pillow in the first hour any more than you'd judge a mattress in the first hour. And don't share one pillow between two positions in the same night if you can avoid it. Side and stomach want different heights. If you switch positions, Rest with a middle setting is the compromise, and compromises have a cost. Know which position you're paying it on.
FAQ
Can a pillow fix a mattress that's too firm?
A little, for the neck, none for the shoulder. If the shoulder is the complaint, the pillow is the wrong layer. Look at the mattress feel. A topper is the layer people mean when they say this, and it has its own limits. See topper or new mattress.
We have different positions. One pillow model?
Buy two. Rest for the person who wants to edit, Keel for the side sleeper who wants the groove. Matching pillows are a catalog idea, not a sleep idea.
Is a more expensive pillow a better pillow?
Not from us. We sell these two. A higher price somewhere else might be fill, brand, or a claim. Read the fill and the return window. Ignore the ranking list.
How we write. Thaw sells the beds named on this page. We don't invent reviews, scores, or studies to make a sale.
If you are already comparing beds
Thaw Rest$79Plush · Adjustable loftShredded fill in a washable shell. Add, remove, sleep.
Thaw Keel$99Medium-firm · About 12 cm at the neckA shaped foam pillow that keeps the neck in line with the spine.
Thaw Drift$849Medium · 25 cm tallA close, quiet foam bed. Shoulders sink. The rest of you stays level.