How to Get Suction Cups to Stick

Choose a smooth, flat surface to apply your suction cup.

Suction cups form an airtight seal on an even surface. Flat surfaces of glass, acrylic, Formica, and stainless steel are all great places to make suction cups stick better. You can even make suction cups stick to plastic as long as it’s a hard surface. The suction cup is more likely to fall if the surface has any slight curves or textures since it could let air into the suction cup and break the seal. If you’re trying to get suction cups to stick in the shower, try putting them on the glass door, a large tile, or on a smooth part of the acrylic wall. For suction-cup phone mounts, avoid putting them on textured dashboards. Try mounting it from your windshield or on your radio display. Suction cups do not work well on porous surfaces, like untreated tiles, fabric, or rough, soft plastics.

Clean the surface you’re sticking the cup to.

Use hot soapy water to remove dust that prevents the cup from sticking. Wet a soft lint-free cloth with warm water and add a dab of dish soap. Scrub the area where you want to stick the suction cup to lift up any dirt or built-up grime that’s on the surface. Rinse the spot clean with some water when you’re finished. If there’s still residue stuck onto the surface, try using vinegar or rubbing alcohol instead since they’re harsher cleaners.

Dry the surface thoroughly.

Your suction cup is more likely to fall if water gets caught inside. Either wipe the area dry with a lint-free cloth or let it air-dry. If you try to press the suction cup down on top of the surface while it’s wet, it will leave air pockets once it dries and weaken the vacuum seal. Marie Kondo, Organizational Expert Thoroughly clean surfaces with rubbing alcohol before applying suction cups, removing any residue. Ensure cups themselves are debris-free; press firmly for 30 seconds to dispel trapped air and maximize seal adhesion. For heavy displays, first moisten cup rims for an even tighter grip. Follow this routine and suction cups will adhere neatly where placed.

Wash the suction cup with dish soap.

Any residue or debris on the suction cup could make it slip. Whether you have an old or new suction cup, wipe it with a damp cloth and a dab of dish soap. Wipe the inside of the suction cup clean with the cloth and rinse it under warm water. Be sure to lightly pat the suction cups dry with a lint-free towel. For any stuck-on residue, try scrubbing the suction cup with vinegar.

Boil old suction cups to revive them.

The heat softens the suction cup so they press onto the surface easier. Fill a pot with enough water to fully submerge the suction cups and bring it to a boil. Take the pot off of heat and drop your suction cups in for about 30 seconds. Take them out with a pair of tongs and pat them dry on a lint-free towel. Try to use the suction cups right after you dry so they’re still warm and flexible.

Stick the suction cup on when the air temp is above 40 °F (4 °C).

Lower temperatures cause air pockets to form inside of the seal. Once air pockets start to form, they weaken your suction cup’s bond with the surface. Wait for the air temperatures to warm up to make your suction cups stronger and get the best results. A good trick to keep suction cups on windows is waiting until warmer spring and summer months so outside temperatures don’t cause them to slip.

Rub petroleum jelly onto the suction cup.

A small dab of petroleum jelly forms an airtight seal. Dip your finger into a tub of petroleum jelly and spread a thin layer around the bottom of the suction cup. When you press the suction cup onto the surface, the petroleum jelly will fill in any gaps and keep water from getting in so you have the tightest seal. In a pinch, you can use any hand lotion instead. Petroleum jelly works great to attach suction cups to glass.

Apply silicone for a more permanent hold.

Silicone dries onto the surface and makes a water-tight seal. Silicone works best on surfaces like glass, hard plastic, and tiles. Get a small tube of waterproof silicone and apply it to the bottom of the suction cup in a spiral pattern. Leave a little free space around the edge of the cup to prevent the silicone from squeezing out. You can buy silicone from your local hardware store.

Press the suction cup down firmly in the middle.

The suction cup will make better contact with the surface for a tighter hold. Hold the suction cup over the surface and push down. Press down hard with your thumb to try and make the suction cup flat against the surface. Pushing against the edges could let air underneath the seal and weaken the suction cup’s hold. If you used silicone and any squeezed out around the edges, quickly wipe up the excess with a damp paper towel.

Wait 24 hours to put weight on the suction cup.

Using the suction cup right away could weaken the seal. Avoid hanging anything or applying pressure to the suction cup right after you put it up. Give the seal a chance to set so it holds firm and doesn’t fall down.

Push down on the suction cup every few days.

Checking on the suction cup helps you catch it before it comes loose. If you want to make suction cups stick forever, you’ll have to check them every few days before they get too weak and fall down. Use your thumb to press down on the middle of the suction cup to get rid of any air bubbles that may have found their way inside. This is called “burping” your suction cups.

Replace suction cups if they have frilled edges.

Frilled edges let in air and make suction cups fall down. The edges of a suction cup only form a tight seal if they’re flat against the surface. If you’ve tried reshaping your suction cups and the edges still lift up from the surface, it’s time to pick up a new one from your local hardware store.