ZINUS 9 Inch Box Spring with Cover
- Box Spring
- Poly jacquard, Steel
- 1
- 1
- Better rated than 91%
- More reviewed than 73%
A practical no-assembly foundation for a queen mattress that needs real height, as long as a compatible bed frame or platform is already in place to hold it.
As an Amazon Associate, ProductDome may earn a commission from qualifying purchases made through links on this page.
Sizes Available
Need a different one? Pick on Amazon →
How it ranks among the 22 box springs we track
4.7★ across 3,900 Amazon ratings, Bayesian-smoothed toward the category average.
3,900 Amazon ratings, weighted on a log scale so huge counts don't drown everything.
200+ bought on Amazon last month.
Brand identity, imagery, description and spec coverage.
The ProductDome score is separate from the Amazon rating shown above: it combines the Bayesian-smoothed Amazon rating with evidence volume, tracked demand, and data quality across the 22 box springs we track - how the scorecard works · full box springs data report. Confidence: high - strong rating volume and complete data.Updated 5 days ago. Data-computed, not a hands-on test. Compiled by the ProductDome Research Team.
Overview
A 9 inch split queen box spring foundation with a poly jacquard cover over a steel frame, sold as a fold flat unit that requires no assembly. It is the foundation only, meant to sit under a mattress on top of a bed frame or platform that is purchased separately.
The selling point is the folding steel structure: it ships flat and unfolds into shape rather than needing tools or hardware, which also makes it easier to carry through hallways and stairwells on moving day. At 9 inches it is built for a high profile look or for shorter mattresses that need extra lift, not a low profile bedroom. Because it is a split queen, it arrives as two pieces rather than one full width unit.
- 9 inch height with poly jacquard cover
- Steel interior frame, no tools to assemble
- Split queen ships as two pieces
- 700 lb combined weight capacity
Who it's for
Suits anyone replacing an old box spring who wants to avoid tools and hardware, especially in apartments with tight stairwells or hallways. Not for platform bed owners, since this is a slatless foundation meant to sit inside a frame that itself provides support.
Strengths and trade-offs
Drawn from this product's published specifications.
- Unfolds with no tools or assembly
- Steel frame rated up to 700 lbs combined
- 9 inch height suits shorter mattresses
- 5 year limited warranty
- Box spring only, needs a separate frame or platform
- Ships as two split queen pieces, not one unit
Performance notes
The interior is steel rather than the wood grid found in older box springs, and Zinus states a 700 lb capacity across the split queen pair (versus 350 lbs for a single twin unit), with the steel frame folding flat for shipping and unfolding on site. The 9 inch height is meant to add lift for mattresses that sit too low or feel too soft without a taller foundation underneath them.
Specifications
| Brand | Zinus |
|---|---|
| Model | SM-SC-BIFD-9Q |
| Dimensions & fit | |
| Item Weight | 48.8 pounds |
| Item Dimensions | 79 × 59.5 × 9 inches |
| Size | Split Queen |
| Construction & materials | |
| Material Type | Poly jacquard, Steel |
| Color | Off-white |
| Included components | |
| Unit Count | 1 |
| Included Components | Assembly Instructions, Hardware |
| Warranty & support | |
| Manufacturer Warranty Description | 5 years |
| Other details | |
| Number of Items | 1 |
| Set Name | Single Set |
| Item Type Name | Box Spring |
| Product Care Instructions | Spot Clean Only |
| Style Name | 9 Inch |
| Shape | Rectangular |
Other Zinus box springs
How it compares
This product against the closest alternatives we track in box springs.
| Product | Amazon rating | Ratings | ProductDome score |
|---|---|---|---|
| ZINUS 9 Inch Box Spring with CoverThis product | 4.7 / 5 | 3,900 | 4.5 / 5 |
| Amazon Basics Smart Box Spring Bed BaseAmazon Basics | 4.4 / 5 | 38,700 | 4.4 / 5 |
| 5 Inch Box Spring for Queen BedTROZULER | 4.2 / 5 | 2,800 | 4.2 / 5 |
| EMODA 5 Inch Box Spring Queen Size Mattress Foundation with Fabric CoverEMODA | 4.2 / 5 | 2,800 | 4.2 / 5 |
| Maenizi 9 Inch Box Spring for Queen BedMaenizi | 4.3 / 5 | 1,600 | 4.1 / 5 |
Similar box springs from other brands
Questions about the Zinus SM-SC-BIFD-9Q
Common buyer questions answered straight from the product spec data - no fluff, no "it depends".
Does this Zinus box spring need assembly?
No. It folds flat for shipping and only needs to be unfolded, with no tools required.
Can this replace a platform bed?
No, this is a box spring foundation only. It needs a bed frame or platform bed underneath it to support it, sold separately.
How much weight can the split queen size hold?
Zinus rates the split queen and other larger sizes up to 700 lbs combined, versus 350 lbs for a single twin unit.