Split King vs Split Top King

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The world of king-sized beds is far more diverse and customizable than most people realize. While many have heard of a traditional king bed, only some are aware of the innovative options available today, such as the Split King and Split Top King (also known as Flex Top) mattresses. These beds offer unprecedented levels of personalization, allowing you to tailor your sleep experience to your needs.

Understanding the differences between these two options can help you to make an informed decision that best suits your sleep preferences. Let’s dive into the details and benefits of each to help you find your perfect match.

Understanding Split King & Split Top King Beds

Split King Bed

A Split King Bed is two Twin XL mattresses placed side by side on a king-sized frame. This setup allows each side to be adjusted independently, making it a favorite among couples with different sleep preferences. Each partner can customize their side of the bed for firmness and elevation without disturbing the other.

Split Top King Bed

A Split Top King Bed, also known as Flex Top, features a mattress split only at the top half. This allows for independent adjustment of the head area while maintaining a unified feel for the rest of the mattress. This option is great for those who want the flexibility of adjustable head positions while still enjoying the feel of a single, cohesive mattress.

Comparison of Split King and Split Top King beds. The image shows the Split King bed with two Twin XL mattresses allowing independent adjustment of both the head and feet for each side. The Split Top King bed is displayed with a single mattress that features independent head elevation for each side while the feet remain unified. Ideal for illustrating the differences in adjustable bed functionality.

Key Differences

The main differences between a Split King and a Split Top King (Flex Top) bed lie in their adjustment flexibility, mattress feel, and bedding compatibility:

Adjustment Flexibility

  • Split King: Offers complete independence for both partners in terms of adjusting the head and foot of the bed.
  • Split Top King: Only the head area is adjustable independently; the foot area remains unified.

Mattress Feel

  • Split King: Because a Split King is made up of two Twin XL mattresses held together on a king frame, some sleepers may feel the split down the middle, especially if you and your partner like to cuddle up. To address this, consider using a bed bridge, such as the bed bridge on Amazon, which fills the gap and prevents sleepers from falling into it.
  • Split Top King: Feels more like a traditional king bed with only the top half split.

Bedding Compatibility

  • Split King: Requires two sets of Twin XL fitted sheets and a king-sized top sheet.
  • Split Top King: Uses specialized split top king sheets that fit the unique shape of the mattress.

Related: Guide to Bed Sizes & Dimensions

Benefits of Each Type

Split King Beds are ideal for couples with differing comfort needs. One partner can have a firm setting while the other enjoys a softer feel. This type also reduces motion transfer, as the beds are separate, and movement on one side is less likely to disturb the other. Additionally, a significant advantage of Split King beds is the flexibility in mattress options. Since you’re essentially buying two Twin XL mattresses, you can choose from almost any mattress brand, providing a wider range of comfort levels, materials, and price points.

On the other hand, Split Top King Beds maintain a cohesive mattress feel for the bottom half, which may be more comfortable for some sleepers. However, one drawback is that Split Top King mattresses are only available in some mattress models, limiting your options.

Choosing the Right Bed for Your Needs

When deciding between a Split King and a Split Top King (Flex Top), consider the following factors:

Sleep Preferences

  • If you and your partner have significantly different sleep preferences, a Split King might be the best choice for maximum customization.
  • A Split Top King could be the perfect solution if you prefer a more unified feel with just the head adjustable.

Bedding and Maintenance

  • Think about the ease of finding and maintaining bedding. Split King beds use Twin XL sheets, which are easy to find.
  • Split Top King beds require specialized sheets, such as Split Top King sheets, which might be less common and more challenging to find.


  • Regarding cost, Split King and Split Top King (Flex Top) beds are often priced similarly by most brands. Therefore, your decision may come down to specific features and personal preferences rather than price differences.
Infographic showing the dimensions of a Split King vs a Split Top King bed. The Split King is depicted with two Twin XL mattresses side by side, while the Split Top King is illustrated with a single mattress that has a top-only split for independent head elevation. Both beds are displayed with measurements for width and length.

Buying Guide and Recommendations

When purchasing a bed, it’s important to consider brands that offer both Split King and Split Top King (Flex Top) options to ensure you find the perfect fit for your needs. Here are three top-rated brands that provide these customizable options:


Known for its advanced adjustable air system and customizable comfort settings, Airpedic mattresses provide excellent support and pressure relief. With dual-sided adjustability, you and your partner can each find your ideal firmness level. For an in-depth look, check out our detailed Airpedic reviews.

Sleep Number

Renowned for its adjustable firmness settings and high-quality construction, Sleep Number offers a premium sleep experience with the flexibility of individual adjustments for each side of the bed. Learn more about its features and benefits in our Sleep Number review.


Combining luxury and customization, Saatva offers both Split King and Split Top King options. The Saatva Solaire, in particular, is highly regarded for its adjustable firmness. You can check out more details and purchase options at Saatva.com.

Final Thoughts

Choosing between a Split King and a Split Top King (Flex Top) bed ultimately depends on your preferences and sleeping habits. Both options offer unique benefits that cater to different needs. You can create your ideal sleep setup by understanding the differences and considering what’s most important for your sleep quality.

For more detailed reviews and comparisons, check out our comprehensive mattress reviews.



A Split King bed consists of two Twin XL mattresses placed side by side on a king-sized frame, allowing for independent adjustment on each side.

Also known as a Flex Top, a Split Top King bed features a mattress split only at the top half, allowing for independent head adjustment while the bottom remains unified.

A Split King is typically better for couples with different sleep preferences because each side can be fully customized independently.

Yes, they require specialized sheets such as split top king sheets, which are less common and more expensive than standard sheets.

Split King beds are widely available as they use two Twin XL mattresses. Split Top King beds are less common and not available in all models.

Yes, some sleepers may feel the split down the middle of a Split King bed, especially if they like to cuddle up in the middle.

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