Sleepeezee ActivFlex Response 1600 Memory Single Mattress
The Sleepeezee ActivFlex Response 1600 is a firm hybrid that pairs 1600 barrel-shaped pocket springs with memory-style foams, which means you get precise, targeted support with a gentle cushioned surface on top.
- Firm support with a softer top
- Cooling gel helps regulate temperature
- Hypoallergenic & vegan-friendly
£699
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Sleepeezee ActivFlex Response 1600 Memory Mattress
More available sizes
Mattress details
Mattress
Sleepeezee ActivFlex Response 1600 Memory Mattress
Size
Firmness
Firm
Construction
Hybrid
Memory Foam
Depth (cm)
25
Layers
5
Layer Details
Soft Knitted Cover
A highly breathable knitted cover that's soft to the touch. It gives the mattress a genuinely luxurious finish.
Pillow Top / Comfort Layer
A soft polyester comfort layer that adds gentle cushioning, which means the surface feels welcoming rather than hard. It does this without compromising the firm feel underneath.
Staycool™ Gel
A deep layer of Staycool Gel that provides a consistently cooling sensation, helping to regulate your temperature. If you're a hot sleeper, this is the layer doing the work for you.
ActivFlex™ Spring Foam
A layer of spring foam that behaves like pocket springs for precise support, yet moulds to your body like foam. The result is support at every point of contact rather than pressure in a few places.
Pocket Springs Core
A core of up to 1600 barrel-shaped pocket springs delivering targeted support to key areas of your body. This is where the firm feel comes from.
Layer details from mattressnextday.co.uk product page, September 2026.
Key benefits
- Full spec, smallest footprint: You get the same ActivFlex spring foam and pocket spring core as the bigger sizes, which means solo sleepers aren't getting a cut-down version.
- Frees up floor space: At 90cm wide it leaves room for a desk, wardrobe and toy storage in a child's bedroom, or a workspace in a spare room that doubles as an office.
- Firm support for growing sleepers: The firm spring core keeps the sleeping surface flat and supportive, which suits children and teens better than a soft mattress they sink into.
- Cool for small rooms: The Staycool Gel layer helps regulate temperature, useful in compact bedrooms and loft rooms that hold heat in summer.
- Works in pairs: Two UK singles plus a walkway suit siblings sharing a room or a guest room set up for two visitors rather than one.
This size suits you if...
You're buying for one sleeper: a child moving up to a full-size bed, a teenager, a student kitting out a first flat, or a guest room. It also makes sense if your room is tight, since the UK single needs only around 2.1m x 2.8m of floor space, and if you want a firm, supportive feel rather than a soft one for a growing sleeper.
Consider another size if...
You're an adult who shares the bed, or you simply want more room to stretch out. We'd recommend the UK double instead, which is 45cm wider and the same length; allow at least 2.6m x 2.8m for it.
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FAQ's
Will the Sleepeezee ActivFlex Response 1600 UK single fit a bunk or mid sleeper?
The 90 x 190cm footprint matches standard UK bunk and mid sleeper frames, so width and length are fine. Depth is the thing to check: this mattress is 25cm deep, and raised frames have a maximum mattress height so the guard rail still does its job. Measure from the base to the top of the rail before ordering.
What room size do I need for the ActivFlex Response 1600 UK single?
We suggest at least 2.1m x 2.8m of floor space. That leaves enough room to walk around the bed and open drawers or a wardrobe. Because the UK single is only 90cm wide, it's the most forgiving size for awkward spaces: box rooms, loft conversions with sloping ceilings, or a spare room that also holds a desk.
Is the UK single ActivFlex Response 1600 a good choice for a child?
In most respects yes: it's firm and supportive, hypoallergenic, and the Staycool Gel helps warm sleepers. One caution: this is a firm mattress, and very lightweight side sleepers can find firm surfaces press on shoulders and hips. For a child who sleeps mainly on their back or front, that firmness is a benefit rather than a problem.
Is a UK single long enough for a tall teenager?
The UK single is 190cm long, the same length as the UK small double and UK double. For most teenagers that's plenty. If you're buying for someone approaching six foot who has years of growing left, it's worth knowing the UK single is 10cm shorter than the UK king, which is 200cm long.
Could two singles work for a shared kids' room or guest room?
Yes, and it's often the more flexible choice. Two UK singles at 90cm wide each can sit against opposite walls with a walkway between, which suits siblings sharing or a guest room that needs to sleep two people who aren't a couple. Compare the retailers listed on this page for the current price per mattress.