Which Foil Balloons Can Be Filled With Helium (And Which Are Air-Fill Only)?

Foil balloons are a popular choice for birthdays, Mother’s Day, Valentine’s Day, baby showers, and event decorations. Their metallic finish, vibrant colours, and themed designs make them perfect for balloon bouquets, gifts, and displays.

However, not all foil balloons are designed to float with helium. Some can be filled with helium, while others are intended to be filled with air only.

Understanding the difference helps ensure your balloons perform as expected and prevents wasted helium or disappointing results.

This guide explains which foil balloons can float with helium, which must be air-filled, and why DIY helium tanks should only be used with latex balloons.

Foil Balloons That Can Be Filled With Helium

Many foil balloons are specifically designed to float when filled with helium. Most of these balloons include a self-sealing valve, which makes them easy to inflate and reuse.

Common helium-fillable foil balloons include:

• Standard foil balloons (usually 18–20 inches)
  These are the classic round, heart, or star balloons commonly used for celebrations. Because of their size, they contain enough helium to float.
• Large number and letter balloons (typically 34–40 inches)
  Oversized foil balloons shaped as numbers or letters can float well with helium due to their large surface area.
• Large shaped foil balloons
  Character balloons, themed designs, or novelty shapes that are large enough can also float when helium-filled.

Important size rule

As a general guide:

• Foil balloons 18 inches (45cm) or larger usually float with helium.
• Smaller balloons may not float, even if filled with helium.

If the balloon is too small, the weight of the foil material can outweigh the lifting power of the helium.

Foil Balloons That Are Air-Fill Only

Some foil balloons are designed strictly for air inflation and will not float, even if helium is used.

Examples include:

• Mini foil balloons (typically 9–14 inches)
  These smaller balloons are often used for floral arrangements, table decorations, cake toppers, garlands, or balloon mosaics. Their size makes them too heavy to float with helium.
• Foil balloon banners or balloon letters on strings
  Many decorative letter banners come with holes or tabs for hanging. These are designed for air inflation and display rather than floating.
• Balloon garlands and balloon wall decorations
  Foil balloons used as part of a balloon garland or installation are usually air-filled and attached to structures or frames.
  

Air-filled foil balloons are often mounted on sticks, attached to ribbon, or incorporated into décor displays.

How To Tell If A Foil Balloon Is Helium-Friendly

If you’re unsure whether a foil balloon can float with helium, check the following:

• Balloon size – balloons 18 inches or larger are more likely to float
• Packaging instructions – manufacturers usually specify helium or air inflation
• Valve type – most helium-compatible foil balloons include a self-sealing valve

If the packaging says “air fill only”, the balloon will not float.

Important: DIY Helium Tanks Are Designed For Latex Balloons

Many people purchase disposable helium tanks for parties at home. While these tanks are convenient, they are typically designed for latex balloons.

Although it’s possible to use DIY helium tanks to inflate foil balloons, it’s not recommended. Foil balloons are heavier than latex balloons and need more helium to float properly. Because Australian safety standards limit the amount of helium in home-use tanks, they are better suited for latex balloons.

New in: We’ve created a range of foil balloons specifically designed to perform better with DIY helium tanks. Discover the range here.

Why DIY helium tanks aren’t ideal for foil balloons

• No foil inflation nozzle
  Latex balloons stretch easily over the nozzle, while foil balloons require a narrow nozzle inserted into the valve. Our tanks can be used for both, but extra care is needed to avoid damaging foil balloon valves.
  

• Lower helium pressure
  Disposable helium tanks usually release helium at a lower pressure, which may not properly inflate foil balloons.
• Risk of damaging the balloon valve
  Forcing helium into a foil balloon without the correct nozzle can damage the valve and cause leaks.

Best practice

If you want to inflate foil balloons with helium, it’s best to use:

• A proper helium cylinder with foil balloon nozzle
• A balloon pump designed for foil valves
• Or have them filled at a balloon or party supply store

For home use, disposable helium tanks work best with standard latex balloons.

Air-Filled Foil Balloons Still Create Beautiful Displays

Even if a foil balloon can’t float, it can still be used creatively in displays.

Air-filled foil balloons are commonly used for:

• Balloon garlands
• Table centrepieces
• Gift decorations
• Photo backdrops
• Shop window displays
• Event installations

Air inflation also allows balloons to last significantly longer than helium-filled balloons.

Final Tips For Choosing The Right Balloon

When selecting foil balloons for your event or display, remember:

• Large foil balloons (18″+) can usually float with helium
• Mini foil balloons are air-fill only
• Always check packaging instructions
• DIY helium tanks are designed for latex balloons

By choosing the right inflation method, you’ll ensure your balloons look their best and perform exactly as expected.