Step 1: Determine if the Mattress Has a Leak

Temporary air mattresses will gradually lose air over time, and should be reinflated before each use to ensure the sleep surface is comfortable and supportive. Cold temperatures can cause mattresses to lose air more quickly, as well, and some newer models may not inflate to their fullest until they have been used a few times. However, there should be a noticeable difference between an air mattress naturally losing air and one with a leak.

If possible, test out an air mattress at least one day before you need to use it. First, inflate it to full capacity. Then, once the mattress is fully inflated, lay down on it as you would when sleeping. If there is a leak, the top surface will likely sag at least one inch.

If you’re still not sure whether there is a leak, place some weight on the mattress and check back in a few hours. If the mattress looks to be fully or mostly inflated, then it most likely does not have any leaks; specifications related to the mattress itself may be to blame for premature deflation. Mattresses that begin to deflate as soon as they are fully inflated, on the other hand, probably have at least one leak.

Step 2: Find the Leak(s)

Leaks tend to be small and difficult to spot with the naked eye. You may be able to locate the leak by reinflating the mattress and listening or feeling for bursts of air. If you still can’t find the leak, then the following measures may work:

• Check the valve: Some air mattresses have valves that consist of two parts: a plug that inserts into an opening called a stem. Others have a dial-style knob that can be tightened.  To check the valve, make sure the valve plug is fully inserted in the stem or the dial is fully tightened. Then inflate the mattress to capacity or place your hand in front of the valve to feel for escaping air. If the plug is inserted but air is leaking, then the plug may be too small; and if the plug will not fully insert, then the issue may be with the valve stem. On dial valves, if the dial is fully tightened but air is still leaking, then there is probably an issue with the seal. If the plug is fully inserted or tightened and you can’t feel any escaping air, then the leak is likely located in a different part of the mattress.
• Prop up the mattress: Not surprisingly, most air mattress leaks are located on the bottom of the mattress due to contact with sharp objects. If the valve seems to be in working order, maneuver the mattress to that it is standing on its side with the bottom surface off the ground, and then listen for hissing sounds and feel for escaping air. If you don’t hear anything at first, place your hand on the surfaces and press down in different areas. Also check the top surface and sidewalls and pay close attention to the mattress seams, since leaks may be harder to see.
• Apply dish soap: This hack requires you to mix liquid dish soap and warm water, and then apply it to the surface of the mattress using a spray bottle or damp wash cloth. Escaping air will cause bubbles to form where the dish soap is applied. First try the valve, and then move on to the top and bottom surfaces and sidewalls.
• Use a hose: The ‘hose’ method involves spraying the valve and surfaces of the mattress with water using a hose spout and watching for bubbles (similar to the dish soap method). Low water pressure is recommended, as high pressure can make the bubbles harder to see and, in extreme cases, may damage the outer layers of the mattress.

Hopefully, you will find the leak(s) using one of these methods. Be sure to mark all leaks with a pen or permanent marker to help you relocate them easily. If you still haven’t found the leak by this time, then you may want to contact the mattress manufacturer or bring the item to the store where it was purchased, as there may be a product defect to blame (see Warranty section below for more information).

Before moving on, a quick word about the ‘submerging’ method. The submerging method — also used to locate leaks in bicycle tires — requires you to completely submerge the mattress in a pool of water, and then remove it to see where water leaks. This can be very effective at finding the leak, but be warned: it can also cause permanent damage to the air chambers of the mattress, the valve and the fabric used to pad the sleep surface. Unless the product manual explicitly says the mattress is safe to submerge, we highly discourage this method.

Step 3: Sand and Clean the Leak(s)

This step is only required if the leak is located in a part of the mattress with fabric or fiber layers. First, deflate the mattress completely. Then, using superfine sandpaper (360 to 600 grit), rub away the fibers surrounding the leak until you reach the rubber surface below. This creates a smooth, uniform surface that is ideal for patching; uneven surfaces may still leak even when patched. If there is dirt or grit on or around the leak, dap at it with a wet wash cloth. Rubbing alcohol can also be used to clean the leak.

Step 4: Dry the Mattress

Before you can patch the hole, the mattress must be completely dry. If you haven’t used the dish soap and/or submerging method, then you can skip this step and begin patching right away. However, if you have used water or rubbing alcohol to find or clean the leak, then it’s best to let the mattress dry for at least two to three hours; placing it in direct sunlight can speed up the drying process. Make sure to fully deflate it before you begin drying if you do not need to sand the leak, as this will help the mattress dry more quickly.

Step 5: Patch the Leak(s)

Many air mattresses come with kits for repairing leaks. If you can’t locate the kit that came with your mattress, some companies — including Therm-a-Rest, REI, and Walmart — sell patch kits specifically designed for air mattresses; a bicycle patch kit will also work in a pinch.

Some patches have adhesive surfaces and can be applied like bandages, while others require you to apply glue or liquid cement to the area around the leak before adding the patch. However they are designed, make sure the patch is flush with the surface of the mattress without any bubbles or sides that stick up.

As soon as the adhesive and patch have been applied, place your hand over it for one minute to ensure it is flat and will not lose stickiness at the edges. Then allow the adhesive to set for at least two hours; placing a flat object on top of the patch can help keep it down during this process. After enough time has elapsed, reinflate the mattress completely and then look and listen for continued leakage. If you don’t need to use the mattress that night, then leave it inflated and check again in the morning; if it is fully or mostly inflated, then the leak has most likely been repaired.

In addition to patch kits, you may be able to repair leaks in your air mattress using the following two methods. However, these two options also carry certain drawbacks.

• DIY patch: You can construct your own patches using a section of thin plastic. Shower curtains are a popular choice, and thin plastic sheeting can work too. The ideal patch will cover the entire leak, as well as the surrounding area that may have been sanded away. For your adhesive, any heavy-duty glue, rubber cement, or epoxy should do the trick. While the DIY patch method is often effective, please note that this may go against the terms of your warranty and result in voided coverage if you need to file a claim down the road.
• Hot glue: Many online guides and tutorials for mending air mattress leaks recommend applying hot glue to the hole using a low-temperature glue gun and then allowing it to dry, forming a makeshift cover. However, this method produces mixed results. If the glue cracks or loses its adhesion anywhere, it can cause the leak to reappear. Furthermore, the hot glue and/or hot glue gun can cause damage to the outer surface of the mattress. And, like the DIY patch method, using hot glue may void the mattress warranty.

If you don’t have a patch kit handy, we recommend using transparent or duct tape to cover the hole. This may not be entirely effective at stopping the leak, but it may slow the deflation enough to last most (if not all) of the night. Plus, tape lives little residue behind and, in most cases, using tape on leaks will not void the warranty.

Air Mattress Warranty: What's Covered and What Isn't

Every air mattress warranty is different. Some warrant against defects for a certain period of time, while others are lifetime warranties that cover the product as long as it is used by the original owner.

In most cases, the warranty will cover leaks and other damage that occurs because the mattress is defective, either due to manufacturing flaws or damage incurred during shipping or delivery. However, it’s important to note that most air mattress warranties will not cover leaks caused by sharp objects, damage to the mattress, or other types of owner misuse.

Additionally, mending a mattress leak with DIY patching, hot glue, or other materials not included in the patch kit that comes with the mattress may void the warranty. Attempting to take apart the mattress in order to repair leaks often results in a voided warranty, as well.

A general rule-of-thumb to follow: if your mattress has a leak that hasn’t been caused by sharp objects or owner-related damage, then you may be able to have it repaired or replaced by the manufacturer for a relatively low cost (often just shipping and handling fees). If the leak is caused by sharp objects or owner-related damage and it is not covered under the warranty, then you should attempt to fix it using the patch kit that comes with the mattress or, alternatively, a patch kit from the mattress manufacturer (which can often be ordered online). Do not attempt otherwise unless you are willing to potentially void your warranty.

Final Checklist

Now that you know how to repair air mattress leaks, let’s briefly look at the materials needed and steps involved.

To repair a mattress leak, assemble the following:

• Dish soap
• Wet wash cloth or liquid dispenser
• Superfine sandpaper (360 to 600 grit)
• Original or replacement patch kit

Once you have the necessary materials, here are the steps to follow:

1. Inflate the mattress and test it to determine if there is a leak.
2. Check the valve.
3. Inspect other areas of the mattress by looking, applying dish soap, or spraying with a hose.
4. Deflate the mattress completely.
5. Sand the area around the leak if there are fabric or fibers.
6. Dry the mattress completely.
7. Patch the leak using patches and adhesive.
8. Put weight on the patch and allow the adhesive to set for at least two hours.
9. If the leak is not corrected, contact the mattress manufacturer or the store where the product was originally purchased.