How to Fill Up a Water Balloon

Filling and Tying a Water Balloon

Stretch the balloon to get it ready for inflation. Before filling your balloon, give it a tug to prepare it. Stretching the balloon will soften the rubber and help it inflate more easily. Don’t get rough with the balloon. You just want to get it ready so it's less likely to pop when you fill it. If you're in a rush, you can skip to filling the balloon with water. Just be sure to keep the water pressure low so it doesn't fill too quickly.

Attach the balloon's opening to a faucet or hose. Carefully slide the balloon's opening over your water source. If you have a narrow nozzle or aplastic funnel, attach the balloon to this instead. Be extra careful when attaching and removing the balloon so as not to tear it.

Turn on the water and keep the pressure low. If you turn the water on full blast, the balloon might fill up too quickly and pop. Fill the balloon until it's about 90 percent full. That way, you'll have enough room to tie the end. While you shouldn't overfill the balloon, make sure the rubber has spread and become thin. If you don't fill it enough, it won't pop when you throw it.

Turn off the water, then remove and tie the balloon. When the balloon is about 90 percent full, turn off the water and carefully slide the opening off of the water source. Pinch the end so water doesn't spill out, then pull it in a loop around your fingers. To make a knot, slide the tip through the loop you made, then pull it tight.

Using a Nozzle

Look for balloons that come with a hose nozzle. Water balloon packages often include nozzle attachments that twist onto threaded hoses and faucets. Don’t underestimate the nozzle’s importance! Using a nozzle or other narrow tool is the key to filling up a water balloon. Filling a balloon by sliding its opening over a metal faucet is risky. Even if the opening fits over the faucet, there’s a good chance the metal will shred it when you try to remove the balloon.

Attach the nozzle, then slide a balloon onto it. Screw the nozzle onto your hose or faucet, then carefully slide a balloon’s opening over it. If the nozzle came with your package, it’s probably just the right size for your balloons. The balloon's opening should fit snugly and slide just enough up the nozzle’s length to allow for proper filling. If you slide a balloon too far up a nozzle or other tool, there won’t be enough room to fill it.

Turn on the water and fill the balloon about 90 percent. Keep the water pressure low so you can turn it off before the balloon pops. The balloon will be ready when the rubber starts to stretch and it’s about 90 percent full.

Turn off the water, remove the balloon, then tie it. Don’t overfill the balloon, and make sure you leave enough room at the end to tie it. When it’s ready, turn the water off and slide the balloon off of the nozzle. To tie it, pull the opening in a loop around your thumb and index finger, then slide the end of the opening through the loop. If necessary, let off a little water so you have room to tie the end.

Store the balloons in a bin filled with water. Fill a plastic bin large enough to hold your balloons about one-third with water. Place each balloon into the bin as you finish them. Storing the balloons in a water-filled bin will help cushion them and prevent accidental popping. If you’d like, keep a few ice packs in the bin to keep the water balloons cold. There’s nothing like a splash of chilly water on a hot day!

Using a Funnel

Use a funnel if you don’t have a nozzle. Don’t worry if you’re stocked with balloons but are missing a faucet nozzle. Look around the house for a medium-sized plastic funnel or buy one from a grocery, department, or hardware store. If the funnel is used for food, wash it thoroughly after using it to fill your balloons. Avoid using a funnel that’s used to pour automotive fluids or other dangerous chemicals.

Stretch a balloon, then slide its opening over the funnel’s tip. Give your balloons a little stretch to prepare them for filling. The balloon should fit snugly over the funnel, but don’t slide the opening more than ⁄2 inch (1.3 cm) up the tip. Take care not to snag the balloon opening on the funnel’s tip.

Pour water into the funnel’s opening. Turn on the faucet, then hold the funnel under the stream of water. Keep the water pressure low so you don’t overfill the balloon. One advantage of funnels is that they’re great for both indoor and outdoor filling. Nozzles typically screw onto threaded outdoor faucets and hoses, so you can't use them on indoor faucets that don't fit or aren't threaded.

Turn off the water, then remove and tie the balloon. When it’s about 90 percent full, pull the funnel out from under the water stream and turn off the faucet. Carefully slide the balloon off of the funnel, then pull the end in a loop around your fingers. Slide the end of the opening through the loop to make a knot.

Filling Balloons with a Tank Sprayer

Purchase a tank sprayer and fill it with water. You can find inexpensive tank sprayers online or at department and hardware stores for under $10 (USD). Fill it up at home, then use it to blow up balloons at another location. In addition to being portable, a tank’s spray nozzle is perfect for filling water balloons. They come in multiple sizes; a 1 gallon (3.8 L) tank makes about a dozen balloons. Water balloons can be tough to transport. If you need to bring some to a park or other location without a water source, filling up balloons on-site will prevent accidental popping during during a car ride.

Use empty jugs filled with water to refill the tank. Gather large milk, juice, or water jugs, rinse them out if necessary, and fill them with water. Bring them along to the park so you can refill the tank and make more balloons. Use the water in the tank to make one batch of balloons, then refill the tank with the jugs and make additional batches.

Prime the sprayer, then fill the balloons. Slide the opening of a balloon over the spray nozzle, then use the handle on the top of the tank to prime it. Pull the spray trigger to fill the balloon with water. Re-prime the sprayer when the stream of water weakens or stops.

Slide the balloon off of the nozzle, then tie the end. When the balloon is about 90 percent full, carefully pull it off of the sprayer. Make a loop with the end, then make a knot by sliding the tip of the opening through the loop. Store your balloons in a water-filled plastic bin to prevent accidental popping.