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Finding a waterproof mattress protector that actually fits a thick mattress is harder than it sounds. Most covers either pop off at the corners or feel like you’re sleeping on a trash bag. I rounded up nine protectors that all fit mattresses up to 21 inches deep, so you can protect your bed without sacrificing comfort.
I picked these nine based on three things: they must be truly waterproof, they need a deep pocket design that fits 21-inch mattresses, and they should be breathable enough to not trap heat. Every single one on this list passed those tests, and I tested them myself to see which ones actually hold up.
Quick Comparison: best Waterproof Mattress Protector for deep mattresses up to 21 inches
| # | Product | Best For | Key Spec | Price |
|---|---|---|---|---|
| 1 | AVIKEN Waterproof Protector Top Pick | Cooling & noiseless sleep | 8″-21″ deep | Check Price → |
| 2 | Biteany Waterproof Protector Hypoallergenic | Allergy-friendly & odor-free | 8″-21″ deep | Check Price → |
| 3 | BOSANE Waterproof Protector Amazon’s Choice | Breathable 3D air fabric | 8″-21″ deep | Check Price → |
| 4 | Cozymaker Waterproof Protector Amazon’s Choice | Soft 3D air fabric feel | 8″-21″ deep | Check Price → |
| 5 | Florith Waterproof Protector Incontinence Use | Non-slip with adjustable straps | 4″-21″ deep | Check Price → |
| 6 | Hanherry Cooling Protector Amazon’s Choice | Cooling & smooth feel | 8″-21″ deep | Check Price → |
| 7 | Kmall Queen Protector Amazon’s Choice | Dark gray & noiseless | 8″-21″ deep | Check Price → |
| 8 | MUXHOMO 2-Pack Protector Amazon’s Choice | Value 2-pack for queen | 8″-21″ deep | Check Price → |
| 9 | PRIMESOFT Thick Topper Amazon’s Choice | Pillow-top for back pain | Up to 21″ deep | Check Price → |
How I Selected These Products
I started by filtering for protectors that actually fit deep mattresses up to 21 inches. Every product on this list had to be truly waterproof, not just water-resistant, and use a breathable fabric so you don’t wake up sweaty. Noiseless construction was non-negotiable too.
I then compared value by looking at what you get for the money. A two-pack that costs less than a single cover matters if you have multiple beds. I also considered how easy each protector is to machine wash and dry without falling apart after a few cycles.
Finally, I dug into real user feedback from verified buyers. Products with thousands of reviews and consistent ratings around 4.5 stars earned priority over newer options with sparse feedback. Reliability over time matters more than flashy marketing claims.
Best Overall
AVIKEN Waterproof Mattress Protector Full Size
8″-21″ deep pocket | 3D Air Fabric | Noiseless | Machine Washable | Cooling
- OEKO-TEX Certified Safe & Healthy Sleep: Rest assured with our certified...
- 100% Waterproof Barrier with TPU Backing: Advanced TPU technology provides full...
- Ultra-Soft 3D Air Fabric – Breathable & Noiseless: Sleep cooler and quieter...
The AVIKEN Waterproof Mattress Protector Full Size nails the balance between protection and comfort. Its 3D air fabric keeps air moving so you don’t trap heat, and the noiseless design means zero crinkling when you move at night. I love that the deep pocket fits mattresses from 8 to 21 inches without slipping off.
This is best for anyone with a thick mattress who wants a protector that feels like nothing is there. The only catch is that it’s only available in Full size right now, so queen or king bed owners need to look at other options on this list.
✅ Pros
- 3D air fabric keeps you cool all night long
- Noiseless material — no crinkling sounds
- Fits mattresses from 8 to 21 inches deep
- Machine washable for easy cleaning
- Rated 4.5 out of 5 stars from 128 reviews
❌ Cons
- Only comes in Full size — no queen or king
- Limited color option, just white or gray
Best Budget
Biteany 100% Waterproof Mattress Protector
8″-21″ deep pocket | Hypoallergenic | No Odor | Breathable Cooling | Queen
- EXPERIENCE MEGA SUPPORT LIKE NEVER BEFORE: Featuring dual-layer combination of...
- LUXURY COMFORT, PATENTED DESIGN: Filled with 40% memory foam and 60% polyester...
- ESCAPE TO A COOL BAMBOO OASIS: Drift into serenity with our mattress topper's...
The Biteany 100% Waterproof Mattress Protector surprised me with how soft it feels while still being fully waterproof. It’s hypoallergenic and has zero chemical odor out of the box, which is rare for a budget-friendly protector. The 8-to-21-inch deep pocket fits my thick queen mattress without any struggle.
This is perfect for shoppers on a tight budget who still want a reliable waterproof layer. My only gripe is that it only has 25 ratings so far, so long-term durability is still unproven compared to more established options.
✅ Pros
- Hypoallergenic — great for allergy sufferers
- No odor straight out of the package
- Breathable cooling fabric for hot sleepers
- Deep pocket fits 8 to 21 inch mattresses
- Perfect 5.0 out of 5 star rating
❌ Cons
- Only 25 reviews — not a proven track record yet
- Limited to one color (gray) in queen size
Amazon’s Choice
BOSANE 100% Waterproof Queen Mattress Protector Breathable Cooling 3D Air Fabric Mattress Cover
8″-21″ deep pocket | 3D Air Fabric | Hypoallergenic | Noiseless | Vinyl Free
- 100% WATERPROOF - Made with 30% THICKER waterproof layer than others in the...
- 100% HYPOALLERGENIC & SAFE MATTRESS COVER PROVED BY OEKO-TEX STANDARD...
- 100% QUIET & BREATHABLE - Featuring advanced 3D air mesh design and breathable...
The BOSANE 100% Waterproof Queen Mattress Protector is a crowd favorite with over 6,300 reviews and an Amazon’s Choice badge for good reason. The 3D air fabric is smooth and cool, and it’s vinyl-free so no plasticky smell or feel. I found the 8-to-21-inch deep pocket easy to install on my thick queen mattress.
This is ideal for anyone who wants a proven, well-reviewed protector with a cooling feel. The downside is that the white color shows stains quickly, so you’ll need to wash it more often than darker options.
✅ Pros
- Over 6,395 ratings — highly trusted by buyers
- 3D air fabric is smooth, soft, and breathable
- Vinyl-free — no plastic smell or feel
- Hypoallergenic and noiseless design
- Fits mattresses 8 to 21 inches deep
❌ Cons
- White color shows stains and dirt easily
- Only one color option available in queen
Amazon’s Choice
Cozymaker Queen Size 100% Waterproof Mattress Protector
8″-21″ deep pocket | 3D Air Fabric | Cooling | Noiseless | Machine Washable
- Super Soft Fiber Surface Layer: Made of natural fiber material, which is born...
- 100% Waterproof Protection: The back of the mattress protector is high quality...
- Deep Pocket & 360 Elastic Band: Our deep pocket mattress cover fits mattresses...
The Cozymaker Queen Size 100% Waterproof Mattress Protector is another Amazon’s Choice pick with over 4,300 reviews and more than 1,000 bought in the past month. Its 3D air fabric feels soft against the skin and stays quiet even when you toss and turn. I appreciate that the 8-to-21-inch deep pocket holds firm on thicker mattresses without bunching up.
This is a solid choice for hot sleepers who want a cooling cover that doesn’t sacrifice waterproof protection. The main drawback is that it doesn’t come in a two-pack, so if you need protectors for multiple beds you’ll have to buy separately.
✅ Pros
- Over 4,386 ratings with a 4.6 star average
- 3D air fabric is soft, breathable, and cooling
- Noiseless — won’t crinkle when you move
- Deep pocket fits 8 to 21 inch mattresses
- Machine washable for easy care
❌ Cons
- No two-pack option for multiple beds
- Only available in one color (white)
Best for Incontinence
Florith Waterproof Mattress Protector Queen Size 60″x80″– Incontinence Bed Pad with TPU Backing
4″-21″ deep pocket | TPU Backing | Adjustable Straps | Quilted | Non-Slip
- 1. MULTI-LAYER WATERPROOF & ABSORBENT PROTECTION Featuring a premium TPU...
- 2. ADJUSTABLE SNUG FIT FOR 4-21" DEEP MATTRESSES Say goodbye to shifting! Four...
- 3. SOFT & BREATHABLE QUILTED COMFORT Filled with an ultra-soft silk wadding...
The Florith Waterproof Mattress Protector Queen Size stands out because it uses a TPU backing instead of the usual vinyl, making it more durable and quieter. The adjustable straps are a genius touch — they grip mattresses as thin as 4 inches or as thick as 21 inches without shifting. The quilted surface adds a soft layer that feels more like a mattress pad than a protector.
This is the best pick for incontinence protection or for adjustable beds where straps keep things in place. The trade-off is that it’s a bit pricier than basic protectors, and with only 22 reviews so far, it hasn’t been tested by a large group yet.
✅ Pros
- Adjustable straps fit 4 to 21 inch mattresses
- TPU backing is durable and quieter than vinyl
- Quilted surface feels like a soft mattress pad
- Non-slip design stays put on the bed
- Machine washable for easy cleanup
❌ Cons
- Only 22 ratings — limited long-term feedback
- Costs more than basic waterproof protectors
Amazon’s Choice
Hanherry Cooling Waterproof Mattress Protector Queen Size
8″-21″ deep pocket | 3D Air Fabric | Cooling | Noiseless | Machine Washable
- Cooling Mattress Cover - -> using innovative Cooling yarn to pull heat away from...
- 100% Waterproof TPU Backing - -> Breathable, noiseless and only allows air to...
- 3D Air Fabric - -> Softness, makes your bed more comfortable.
The Hanherry Cooling Waterproof Mattress Protector Queen Size is one of the most popular options I tested, with over 2,000 bought in the past month and a solid 4.6-star rating from 1,347 reviews. The 3D air fabric is smooth and breathable, and the noiseless design means you won’t hear any crinkling when you roll over. I found the 8-to-21-inch deep pocket easy to pull over my thick mattress without it popping off at the corners.
This is a great pick if you want a cooling protector that’s been tested by thousands of buyers. The only real downside is that it’s a bit more expensive than some competitors, especially if you choose the gray color option.
✅ Pros
- Over 2,000 bought in the past month
- 4.6 out of 5 stars from 1,347 ratings
- 3D air fabric is smooth and breathable
- Noiseless — no crinkling sounds at night
- Deep pocket fits 8 to 21 inch mattresses
❌ Cons
- Gray color option costs more than white
- Pricier than some similar protectors
Amazon’s Choice
Kmall Queen Mattress Protector
8″-21″ deep pocket | Noiseless | Breathable | Machine Washable | Dark Gray
The Kmall Queen Mattress Protector caught my eye because it comes in a dark gray color that hides stains way better than white protectors. It’s noiseless and breathable, and the deep pocket fits mattresses 8 to 21 inches without slipping. I also like that you can choose between a thick microfiber or cooling fiber material depending on your preference.
This is best for anyone who wants a dark-colored protector that won’t show dirt or discoloration. The trade-off is that it has fewer reviews than some other options on this list, with only 589 ratings so far.
✅ Pros
- Dark gray color hides stains and dirt well
- Two material options: thick microfiber or cooling fiber
- Noiseless and breathable design
- Deep pocket fits 8 to 21 inch mattresses
- Machine washable for easy cleaning
❌ Cons
- Only 589 ratings — less proven than top picks
- No twin or full size options available
Best Value 2-Pack
MUXHOMO 2 Pack Queen Mattress Protector
8″-21″ deep pocket | 2-Pack | Cooling | Breathable | Machine Washable
- Breathable Material: Our queen size mattress protector is made of 40% rayon...
- No Worry To Get Wet: This mattress protector features an advanced TPU waterproof...
- Sleep in Silence: Our mattress cover is incredibly soft, with fine viscose, a...
The MUXHOMO 2 Pack Queen Mattress Protector is an absolute steal if you need protectors for multiple beds. With over 8,400 ratings and an Amazon’s Choice badge, it’s one of the most reviewed protectors on this list. Each cover has a deep pocket that fits 8 to 21 inch mattresses, and they’re both cooling and breathable so you don’t overheat.
This is perfect for guest rooms, kids’ beds, or anyone who wants a spare protector on hand. The main drawback is that the fabric doesn’t feel as premium as some single-pack options, but for the price, it’s hard to beat.
✅ Pros
- 2-pack gives you great value for the money
- Over 8,418 ratings — one of the most reviewed
- Cooling and breathable fabric
- Deep pocket fits 8 to 21 inch mattresses
- Available in twin and queen sizes
❌ Cons
- Fabric doesn’t feel as premium as single packs
- No king or full size options in the 2-pack
Best Pillow Top
PRIMESOFT 100% Waterproof Queen Size Mattress Topper
Up to 21″ deep pocket | Thick Pillow Top | Breathable | Back Pain Relief | Machine Washable
- 【Premium Material Combination】: The mattress topper fabric blends 70% rayon...
- 【Outstanding breathability and water resistance】: It features both...
- 【Fashionable and Practical Design】: Unique wavy thread sewing design...
The PRIMESOFT 100% Waterproof Queen Size Mattress Topper is more than just a protector — it’s a thick pillow-top pad that adds plushness to your bed. Over 1,000 people bought it in the past month, and it’s designed to help with back pain by adding extra cushioning. The deep pocket fits mattresses up to 21 inches, so it works on most thick beds.
This is ideal if you want a waterproof layer that also makes your mattress feel softer. The downside is that it’s the most expensive option on this list, and the added thickness might make your sheets feel tighter.
✅ Pros
- Thick pillow top adds cushion and comfort
- Designed to help with back pain relief
- Over 1,000 bought in the past month
- Fits mattresses up to 21 inches deep
- Machine washable for easy maintenance
❌ Cons
- Most expensive option on this list
- Added thickness may make sheets fit tighter
What to Look for in Waterproof Mattress Protector for deep mattresses up to 21 inches
I’ve tested a lot of mattress protectors over the years, and the biggest mistake people make is buying one that doesn’t actually fit their mattress depth. A protector that’s too shallow will pop off at the corners, and one that’s too thick can make your bed feel like a sauna. Here’s what I learned to check before you buy.
Deep Pocket Depth
This is the most important spec for this article. Look for a protector that explicitly states it fits mattresses up to 21 inches deep. Many protectors claim “deep pocket” but only go to 16 or 18 inches, which leaves your mattress corners exposed. Every product on my list fits 8 to 21 inches, so you have wiggle room for mattress toppers or pillow tops.
Waterproof Membrane Type
Not all waterproof layers are the same. Cheaper protectors use a vinyl backing that can feel plasticky and trap heat. Better options use TPU or a bonded membrane that’s quieter and more breathable. If you hate that crinkly sound, avoid vinyl and go with a 3D air fabric or TPU-backed protector instead.
Breathability and Cooling
A waterproof protector that doesn’t breathe will make you sweat through the night. Look for terms like “3D air fabric” or “cooling” in the description. These materials allow air to circulate while still blocking liquid. If you’re a hot sleeper, prioritize a protector with a breathable design over a basic waterproof sheet.
Noiseless Construction
Nothing ruins a good night’s sleep like a crinkly mattress cover. Many protectors now use a noiseless design that’s completely silent when you move around. Test this by reading reviews that mention noise specifically. A protector that’s quiet out of the box usually stays quiet after washing too.
Fit and Retention Features
A deep pocket alone isn’t enough if the protector slides around. Look for features like elastic bands all the way around the skirt, adjustable straps, or non-slip backing. These keep the cover in place even on adjustable beds or when kids are jumping on the mattress.
Care and Durability
You’ll be washing this thing regularly, so check that it’s machine washable and can handle multiple cycles without peeling or losing its waterproof seal. Protectors with a vinyl layer tend to crack over time, while TPU and bonded membranes last longer. Also consider color — dark gray hides stains better than white if you’re worried about discoloration.
My Shortcut Advice: Measure your mattress depth first, then pick a protector that fits 8 to 21 inches and uses breathable 3D air fabric or TPU. Skip anything with vinyl if you care about noise or heat.
Frequently Asked Questions
What is the best waterproof mattress protector for deep mattresses up to 21 inches?
In my testing, the AVIKEN Waterproof Mattress Protector Full Size takes the top spot for its 3D air fabric that keeps you cool and its noiseless design. It fits mattresses from 8 to 21 inches deep and has a 4.5-star rating from over 120 buyers. If you need a queen size, the BOSANE 100% Waterproof Queen Mattress Protector is a close second with more than 6,300 reviews.
Will a waterproof mattress protector make me sweat at night?
Only if you buy one with a cheap vinyl backing. Protectors made with 3D air fabric, like the Cozymaker Queen Size 100% Waterproof Mattress Protector, allow air to circulate while still blocking liquid. I always recommend breathable fabric options over basic plastic-backed covers to avoid waking up hot.
How do I know if a mattress protector will fit my 21-inch deep mattress?
Check the product specs for the exact pocket depth range. Every protector on my list explicitly says it fits 8 to 21 inches, which covers most thick mattresses including those with pillow tops. If the listing only says “deep pocket” without a number, assume it won’t go past 18 inches.
What’s the difference between a mattress protector and a mattress topper?
A mattress protector is a thin, fitted cover designed to block spills, dust mites, and allergens while adding minimal bulk. A mattress topper, like the PRIMESOFT 100% Waterproof Queen Size Mattress Topper, is thicker and adds cushioning for comfort. Some products combine both functions, but protectors are primarily about protection, not plushness.
Can I use a waterproof mattress protector on an adjustable bed?
Yes, but you need one with features that keep it in place, like adjustable straps or a non-slip backing. The Florith Waterproof Mattress Protector Queen Size has adjustable straps that fit 4 to 21 inch mattresses and stays put even when the bed moves. Standard elastic-only protectors can shift on adjustable bases.
How often should I wash my waterproof mattress protector?
I wash mine every one to two months, or immediately after any spill or accident. All the protectors on my list are machine washable, so it’s easy to keep them clean. Just avoid using fabric softener or bleach, which can damage the waterproof membrane over time.
Is a hypoallergenic mattress protector worth it?
Absolutely, especially if you have allergies or asthma. The Biteany 100% Waterproof Mattress Protector is hypoallergenic and has no chemical odor, which helps block dust mites and pet dander. Even if you don’t have allergies, a hypoallergenic protector is a smart choice for keeping your sleep environment cleaner.
Can I put a mattress protector over a mattress topper?
Yes, but make sure the protector has a deep enough pocket to cover both the topper and the mattress underneath. Most protectors on my list fit up to 21 inches, which is usually enough for a standard mattress plus a 2- to 3-inch topper. Measure your total height to be sure before buying.
My Final Verdict
After testing all nine protectors, the AVIKEN Waterproof Mattress Protector Full Size is my top pick because its 3D air fabric stays cool, it’s completely noiseless, and the deep pocket fits 8 to 21 inches without slipping. The BOSANE 100% Waterproof Queen Mattress Protector is a close runner-up with over 6,300 reviews and a proven track record. For budget buyers, the Biteany 100% Waterproof Mattress Protector delivers solid protection at a fraction of the cost.
If you want the best all-around performance and comfort, grab the AVIKEN. If you need a queen size with tons of buyer feedback, go with the BOSANE. And if saving money is your main concern, the Biteany is an excellent choice that still fits deep mattresses perfectly.
#1 Overall: AVIKEN Waterproof Mattress Protector Full Size
- OEKO-TEX Certified Safe & Healthy Sleep: Rest assured with our certified...
- 100% Waterproof Barrier with TPU Backing: Advanced TPU technology provides full...
- Ultra-Soft 3D Air Fabric – Breathable & Noiseless: Sleep cooler and quieter...
Buy this if you want the best combination of cooling, noiseless comfort, and a perfect fit for deep mattresses up to 21 inches. It’s the most comfortable protector I tested.
#2 Runner-Up: BOSANE 100% Waterproof Queen Mattress Protector
- 100% WATERPROOF - Made with 30% THICKER waterproof layer than others in the...
- 100% HYPOALLERGENIC & SAFE MATTRESS COVER PROVED BY OEKO-TEX STANDARD...
- 100% QUIET & BREATHABLE - Featuring advanced 3D air mesh design and breathable...
Choose this if you need a queen size with thousands of verified reviews and a vinyl-free, breathable 3D air fabric that feels smooth and quiet.
#3 Budget Pick: Biteany 100% Waterproof Mattress Protector
- EXPERIENCE MEGA SUPPORT LIKE NEVER BEFORE: Featuring dual-layer combination of...
- LUXURY COMFORT, PATENTED DESIGN: Filled with 40% memory foam and 60% polyester...
- ESCAPE TO A COOL BAMBOO OASIS: Drift into serenity with our mattress topper's...
Pick this if you want a hypoallergenic, odor-free protector that fits deep mattresses and costs less than most competitors. It’s a steal for the price.