- 180-NIGHT HOME TRIAL & 10 YEAR MANUFACTURER WARRANTY – Rest easy with a Siena mattress. You’ll enjoy a 180-night home trial, and we stand by our product – if there’s any defect or flaw in your Siena in the first 10 years, we’ll replace or repair it for free.
- FIVE LAYERS OF COMFORT – Siena doesn’t compromise on comfort. We might cost a lot less than our competitors, but your Siena mattress sure packs a punch when it comes to responsive comfort, supporting proper spinal alignment, and relieving pressure points. With lots of motion-reducing foam, you won’t be disturbed if your partner or pet moves.
- MEDIUM FIRM AND SUPPORTIVE – Finding the perfect firmness is a breeze with Siena. It’s medium-firm, striking the ideal balance between comfort and support for a restful night’s sleep.
- SIMPLE TO SET UP – Just move the box to the room you want to use it in, unbox and unroll your mattress, and watch it expand before your eyes. Your Siena will be snooze-ready in 24 hours!
- CertiPUR-US CERTIFIED – Your Siena meets all CertiPUR-US rigorous standards for materials, emissions, product durability and performance. This is an assessment made by independent, accredited testing laboratories. It means your Siena is made without ozone depletors, mercury, lead, formaldehyde, phthalates and other harmful substances that can be in consumer products.
- SAFE & FIBERGLASS FREE – Your Siena mattress is made without ozone depletors, mercury, lead, formaldehyde, phthalates and other harmful substances that can be in consumer products
-15%New
Siena 12″ King Memory Foam Mattress – Medium Firm – 180 Night Trial – Premium Pressure-Relieving Layers – 10 Year Warranty – Mattress in a Box – CertiPUR-US Certified
$389.00 Save:$70.00(15%)
Available in stock
Last updated on July 6, 2025 6:26 am Details
Description
Additional information
| size | King |
|---|---|
| Special Feature | Simple to Set Up, Durable, Pressure Relief, Adjustable, Breathable |
| color | White |
| Upholstery Fabric Type | Polyester Blend |
| Brand | Siena |
| Included Components | Mattress |
| Item Weight | 75 pounds |
| Age Range Description | Adult |
| Product Care Instructions | Hand Wash Only |
| Manufacturer | Siena Mattress |
| UPC | 810167463767 |
| Product Dimensions | 80 x 76 x 12 inches |
| Country of Origin | USA |
| Item model number | snfmtwlvbz-s:king |
| Thickness | 12 Inches |
| Refill | Memory Foam |
| Batteries required | No |
Reviews (609)
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Lindsey Bishop –
I’ve had the 12” twin XL mattress for almost a month now and it’s the best thing ever. It says 24 hours required to let it fully expand but honestly it seemed ready to go immediately. The packaging was very easy and compact enough to carry it into my second story alone. Incredibly
simple. It’s very very very very comfortable
Thomas D. Stade –
It would be interesting to see how they package this mattress in the factory – unboxing was an experience! There was a label over the QR code that had the instructions, but I found it was unnecessary. Once you pry up each of the flaps (3 on each end that are glued to one another with some heavy duty glue) and push the mattress out from one end (you really do need 2 people – one to push and the other to hold the box), and start unwinding it from it’s plastic wrap, you begin to understand how much the mattress is compressed! Make sure you have plenty of space as this mattress really grows! A true wonder.
Enough of unboxing – this mattress is really quite good for a budget price, with sufficient support and comfort, and seems to be made very well. Sienna is the budget sister product to Nector, which is highly rated for a mid-price range memory foam mattress. I figured I couldn’t go wrong with their less expensive Sienna brand. I think I made a great choice as it was clear the quality and attention to detail was top notch despite it being the budget brand. I highly recommend this mattress for a less expensive option. Read Tom’s Guide for a comparison of the two brands.
adam stash –
Thinking about it I am comfortable leaving this mattress a 4.6/5. Bought this for my son’s room who comes home from college during breaks. We just moved into a new house and I replaced his bed and mattress to a more modern looking one. Gave myself a 500$ budget and after an hour or tow of investigating on line I took a shot because of the positive reviews.
We are now in the new house and he won’t be home until next week and we have to use his mattress because our king mattress has not been delivered yet. I am
Impressed with the quality and would recommend. If I were buying something for myself I would go softer.
angie –
I read a million reviews. I’m the type that wants a soft cloud to lay on and THIS is it!
I didn’t wait the full 72 hours til i slept on it so it only came to 8” thick (bought the 10”) so we
shall see if it’s fully 10 when time goes by but omg if you are looking for a soft bed this is it!
Salomon Guevara –
I bought two 10-inch memory foam mattresses from Amazon – one queen and one full. Ikea bedframes are the foundations for each. They’re comfortable in the side and stomach sleeping positions even though they’re on the firm side, at least for me because I’m tall – 6’4″ and thin -160 pounds. Changing sleeping positions is relatively easy to do, however, I’ve noticed that this requires slightly more effort than with traditional ‘bouncy’ innerspring mattresses due to their minimal motion transfer. I’m hoping that these mattresses will remain completely flat in the unloaded state after hundreds of hours of use. And if so, will be excellent values for the price.
Amazon Customer –
Great mattress for the price. It is on the firmer side, which I wanted. Provides good support but is still very comfortable. I ordered 2 of these for a king size bed and they work great! They expanded immediately after taking out of the the bag and I followed the instructions to let them continue to expand for a day before using. Honestly, though, I think they would have been fine to use after the first 15 minutes. Also, I didn’t notice any weird or offensive smell, and I tend to be quite sensitive to odors. Not sure how long they’ll hold up, but for now I’m very pleased.
Mason Lyon –
Excellent very comfortable and super comfortable I wouldn’t want to get up in the morning but it’s time to work
angie –
Why did you pick this product vs others?:
Perfect mattress for the price range. I’ve been using it for nearly two years and I still love it. Have recommended it to others who also love it.
I initially found this mattress from a mattress reviewer on Reddit, it was the top listed of the cheapest mattress category.