Gainsborough Mayfair 1000 Pocket Ultra Firm Mattress
The Gainsborough Mayfair 1000 Pocket Ultra Firm Mattress pairs 1,000 pocket springs with a dense polyester pad, which means you get a flat, extra-firm feel with support that adapts to your body.
- Very firm, flat sleeping surface
- Minimises partner disturbance
- Cover that doesn't hold heat
£464
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The Gainsborough Mayfair 1000 Pocket Ultra Firm is a pocket-sprung mattress with an extra-firm feel, a 29cm depth and polyester fibre fillings under a damask cover. It suits people who want a very firm, flat sleeping surface. It comes in UK Small Double, Double and King. Mattress Online offers a 100-night trial, and Gainsborough gives a 10-year guarantee.
Mattress specifications
Firmness
Extra Firm
Type
Pocket Spring
Depth (cm)
Number of Layers
Trial Period (nights)
Warranty (years)
Price Range
£464
Best Sleeping Position(s)
Stomach Sleeping
Certifications
Why should you choose this mattress?
The main draw is the firmness. A dense polyester pad sits above the springs to firm up the surface, so you sleep on top of the mattress rather than sinking into it. Each of the 1,000 springs (a count based on the king size) sits in its own fabric pocket and moves independently, which means less movement carries across the bed if your partner shifts in the night. The damask cover doesn't retain heat, and the pad is breathable. It should suit back sleepers and anyone who likes a firm, supportive bed, although it's firmer than most people need.
Key features & layer details
Damask cover
A finely woven, durable fabric that's soft to touch and doesn't retain heat. That means a comfortable surface that stays fairly cool.
Soft White Fibres
A soft synthetic polyester filling that's durable and resilient and keeps its shape. It adds a cosy feel on top of the firm base.
Dense polyester pad
A dense, breathable polyester pad that firms up the feel and adds airflow. It helps keep the surface flat and the mattress lasting longer.
Pocket springs
A core of 1,000 pocket springs, counted on a king size, each in its own fabric pocket. They move independently to give support suited to your body and reduce motion transfer.
Layer details from mattressonline.co.uk product page, October 2026.
Best suited for?
Back sleepers
The extra-firm feel and dense polyester pad keep the surface flat, so you sleep on top of the mattress rather than sinking into it.
Couples
Each of the 1,000 springs (counted on a king) sits in its own fabric pocket, which means less movement carries across the bed when a partner shifts.
Warm sleepers
The damask cover doesn't retain heat and the dense polyester pad is breathable, so the surface should stay fairly cool through the night.
If you prefer a softer, more cushioned feel, this might not be the best choice. It's rated extra firm, and the dense polyester pad firms it up further, so there's little give at the shoulders and hips. Side sleepers, particularly lighter ones, may find it too hard. It also has no foam or latex comfort layer.
Save on an earlier or ex-display model
Some retailers still sell the earlier version of this mattress, or ex-display and returned stock at a lower price. These are the sizes where it costs less than the current model's best price.
Gainsborough Mayfair 1000 Pocket Ultra Firm Mattress
Last seen for £464 at Mattress Online on 25th June 2026
Last seen for £538 at Mattress Online on 25th June 2026
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FAQ's
How firm is the Gainsborough Mayfair 1000 Pocket Ultra Firm?
It's rated extra firm, and the dense polyester pad above the springs adds to that feel. It suits sleepers who want a very firm, flat surface, but side sleepers who like some cushioning at the shoulders and hips may find it too hard.
What sizes does the Gainsborough Mayfair 1000 Pocket Ultra Firm come in?
It comes in UK Small Double, UK Double and UK King. Check the size you need before ordering, as the 1,000 spring count is based on the king size, so smaller sizes will have fewer springs.
How deep is the Gainsborough Mayfair 1000 Pocket Ultra Firm?
It's 29cm deep. That's a fairly standard height for a pocket-sprung mattress, so it should work with most bed frames, though check that fitted sheets suit that depth.
Does the Gainsborough Mayfair 1000 Pocket Ultra Firm have a trial or guarantee?
Mattress Online offers a 100-night trial, which is the retailer's own offer. Gainsborough also provides a 10-year guarantee. Check the retailer's terms before buying so you know how returns work.
Is the Gainsborough Mayfair 1000 Pocket Ultra Firm good for couples?
It can be, if you both want a very firm bed. The springs sit in individual fabric pockets and move independently, which reduces motion transfer. If either of you prefers a softer feel, it's likely to be too firm.
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