by Quick answer: An RV king is typically 72 inches wide, four inches narrower than a residential Eastern King (76 in). Length varies by manufacturer: 75 in or 80 in are both common, and some makers use non-standard cuts entirely. Measure your existing RV mattress before ordering anything. A standard home king almost never fits an RV platform.
By the MattressNut editorial team · Updated June 2026
RV King vs. Residential King: The Size Gap That Matters
RV bed platforms are built around coach dimensions, not bedroom furniture standards. The result is that an "RV king", sometimes called an "RV short king", is a genuinely different size from the Eastern King sold at every mattress store.
Common dimensions at a glance
| Mattress type | Width | Length |
|---|---|---|
| Residential Eastern King | 76 in | 80 in |
| RV King (common variant A) | 72 in | 80 in |
| RV Short King (common variant B) | 72 in | 75 in |
| Manufacturer-specific cuts | Varies | Varies |
The 72-inch width is a reasonable starting assumption, but length is genuinely unpredictable. Some coaches run 78 inches, some 76, some 75. A few manufacturers cut platforms to odd dimensions to fit around wheel wells or storage compartments. This is why the only reliable measurement is the one you take yourself, pull the existing mattress, measure the platform opening, and note width, length, and clearance height.
Residential king sheets will not fit an RV king either. Fitted sheets sized for a 76 × 80 mattress will bunch or pop off a narrower surface. Look specifically for RV king or short king bedding.
What to Look For in an RV King Mattress
Material and weight
Memory foam and gel foam are the most practical choices for an RV king. Both are lightweight relative to hybrids or innerspring builds, which matters because your RV has a gross vehicle weight rating (GVWR), the total allowable loaded weight. A queen-sized foam mattress might weigh 60–75 lbs; a comparable innerspring hybrid can push 100–130 lbs. On a smaller coach, that difference has real consequences for payload capacity.
Foam also handles road vibration better than coil systems. Springs that work quietly in a static bedroom can creak and compress unevenly after repeated travel. For most RV sleepers, an all-foam build is the simpler, lighter, more durable option.
If you prefer a hybrid for the feel, check the mattress weight specification before ordering and calculate it against your remaining payload budget.
Profile and fit
RV bed platforms often sit against a wall, have slide-out components, or are surrounded by cabinets. Getting a thick mattress into position can require maneuvering it through tight corners. A profile of 8–10 inches is manageable in most coaches; anything taller can be genuinely difficult to install and may affect under-bed storage access. Measure clearance from the platform surface to any overhead obstruction before committing to a thick build.
Some RV kings come split into two narrow sections, each roughly 36 × 75 or 36 × 80, to make installation easier and allow independent adjustment for two sleepers. If your platform is accessible from only one side, a split king is worth considering.
Off-gassing before you travel
Memory foam and gel foam release a noticeable odor when first unpacked. In a home, you open windows and let it air out for a day or two. In an RV, the enclosed space concentrates that smell. Unbox the mattress at home, or with all RV windows and vents open, and let it off-gas for at least 48 hours before sleeping on it or closing up the coach for travel.
Measuring Your RV Platform: A Practical Checklist
Before placing any order, take the following measurements from the actual platform opening, not from a manufacturer spec sheet or a previous mattress label:
- Width: measure at the head, middle, and foot, platforms are not always perfectly parallel
- Length: measure on both sides if the space is asymmetrical around wheel wells
- Clearance height: distance from platform surface to any overhead cabinet, wall, or bunk above
- Corner access: if the bed is against two walls, note the tightest opening the mattress needs to pass through during installation
- Slide-out clearance: if the bed is on a slide-out, confirm the mattress clears the wall when the slide is retracted
Write these numbers down and keep them when ordering. RV mattress return policies vary, and shipping a mattress back is expensive. Getting the measurements right the first time is the only practical approach.
Our Top Pick
For RV sleepers who want a purpose-built option rather than a resized home mattress, the PlushBeds MobilePlush is designed specifically for RV dimensions. That makes the sizing and fit more predictable than ordering a standard foam mattress and hoping it matches your platform. Confirm your exact measurements against the sizes PlushBeds offers, and check current pricing on their site.
Check the PlushBeds MobilePlush RV mattress
For a lower-cost comparison, Sweetnight offers foam mattresses across a range of sizes including RV-specific cuts: see Sweetnight's mattress range.
Frequently Asked Questions
What size is an RV king mattress?
Most RV kings are 72 inches wide. Length is less consistent, 75 and 80 inches are both common, and some manufacturers use 76 or 78 inches. The width alone distinguishes it from a residential Eastern King (76 in wide). Because there is no single RV industry standard, the only reliable measurement is the one you take from your actual coach platform.
Will a regular king mattress fit in an RV?
Almost never. A standard Eastern King is 76 inches wide; most RV king platforms are 72 inches. The mattress would overhang by at least four inches, enough to prevent the slide-out from functioning or the frame from closing properly. Even if you trimmed a home mattress, the internal structure would be compromised. Buy a mattress sized for your RV platform, not a residential bed resized to approximate it.
Is an RV king the same as an RV short king?
The terms are used interchangeably by many retailers, but they sometimes indicate different lengths. "RV short king" often refers to a 72 × 75 configuration, while "RV king" may indicate 72 × 80. Neither is an official standard. Check the exact dimensions listed in the product specs and compare them to your platform measurements rather than relying on the label alone.
What type of mattress works best in an RV?
Memory foam and gel foam are the most practical for most RV owners. They are lighter than hybrids (relevant for payload), absorb road vibration without coil noise, and compress enough to maneuver through tight installation spaces. A hybrid works if you prefer the feel and your GVWR allows the added weight, but check the mattress weight spec first. Innerspring-only builds are uncommon in RV-specific mattresses and not the best fit for travel conditions.
How thick should an RV king mattress be?
8 to 12 inches covers most situations. Thinner profiles (6–8 in) work well when clearance is tight, under an overhead cabinet or in a cab-over bunk. Thicker builds (10–12 in) are more comfortable for most sleepers and practical when clearance allows. Measure the height from your platform surface to any overhead obstruction and subtract an inch or two for bedding before choosing a profile.
Do I need special sheets for an RV king?
Yes. Standard residential king fitted sheets are sized for a 76 × 80 inch mattress and will not fit a 72-inch-wide RV king. The sheet will be loose on the sides and likely pop off the corners during sleep. Look specifically for "RV king" or "short king" fitted sheets and confirm the width dimension matches your mattress before ordering.
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Related: our full best RV mattress guide.