Siena Signature 10" Memory Foam review

Siena is the cheapest way we found to get a king that still comes with terms worth trusting. The 10-inch Signature king cost $399 on Siena's US store when we checked, less than half the price of our top two picks, and it ships with a 180-night home trial, free shipping and returns, a 10-year warranty and a 30-day price match guarantee. Siena describes four layers, including 2 inches of contouring memory foam and a stability foam base, and says its foam layers absorb motion so movement stays on one partner's side. The foams are CertiPUR-US certified and the construction is fiberglass free. The catch is depth. A 10-inch all-foam bed with 2 inches of memory foam is a simple build, and two adults who are heavier, or who sit on the edge often, may feel the limits sooner than on a hybrid. Siena sells 12-inch and 14-inch versions for buyers who want more cushioning at a still modest price.

Who it is for

Couples who need a king at the lowest price that still comes with a long trial and a real warranty.

Price

King $399 when checked.

King $ 399 Add To Cart
Quoted from the vendor pricing page on November 10, 2026.

Key features

• Four layers in a 10-inch profile, including 2 inches of contouring memory foam
• Stability foam base layer and a durable outer cover
• CertiPUR-US certified foams and fiberglass-free construction
• 180-night home trial with free shipping and returns
• 10-year warranty and a 30-day price match guarantee

Strengths and weaknesses

• Strength: Cheapest verified king price on this list at $399
• Strength: 180-night trial, longer than most budget brands offer
• Strength: Foam layers that Siena says keep movement on one side of the bed
• Weakness: Only 2 inches of memory foam, thin for heavier couples
• Weakness: No coils, so less bounce and edge support
• Weakness: Shorter trial and warranty than Nectar or DreamCloud

Key facts

• King price: $399 when checked
• Type: Memory foam, 10 in, 4 layers
• Trial: 180 nights
• Warranty: 10 years

Where it ranks

Siena Signature 10" Memory Foam is No. 3 in our Best King Mattresses for the Money verdict and No. 5 in Best Memory Foam Mattresses.