TSA treats hairspray as an aerosol. And aerosols have certain restrictions when packed in luggage.
In hand baggage, you have to pack hairspray in your 1-quart bag of toiletries. It also has to be 3.4 oz (100 ml) or smaller.
In checked bags, hairspray is allowed, but in 18 oz (500 g) containers or smaller. Each passenger can bring up to 70 oz (2 kg) of hazardous toiletries in total (aerosols, perfume, hand sanitizer, nail polish, etc).
TSA also requires you to always have a protective cap over the release nozzle of your hairspray. They ask this because hairspray is flammable, and accidental release of it could become a fire risk under the right conditions.
Traveling With Hairspray Internationally
The rules for traveling with hairspray are identical across the world. The only exception is for countries and airports that have the new 3D scanners, with which liquids and aerosols aren’t limited to 3.4 oz quantities in hand baggage anymore.
On domestic flights in New Zealand and Australia, hairspray is allowed in containers over 3.4 oz in hand baggage. This also applies to some airports in the US and UK, which have the new 3D scanners.
Another thing to remember is that the restrictions for your toiletry bag are usually stricter in other countries compared to the US. So instead of a reusable toiletry bag, you should pack hairspray in a 20×20 cm, 1 liter Ziploc bag.
Aerosol Hairspray vs Non-Aerosol Hairspray
Some hairspray comes with hand-release pump nozzles, instead of an aerosol can. The rules for it in hand baggage are identical because it’s a liquid. In checked baggage, the 2 kg (70 oz) limit doesn’t apply to non-aerosol hairspray because it isn’t considered hazardous.
Hairspray Won’t Explode on Planes
Hairspray, shaving cream, and other aerosols used to explode when packed in checked baggage. A few decades ago, the cargo hold wasn’t pressurized on airplanes. This caused the release mechanism to break from pressure changes, which caused the contents of the aerosol can to pour out.
Nowadays, cargo compartments are pressurized because some passengers travel with pets in the cargo hold. This doesn’t cause any pressure changes, so any aerosols packed in checked baggage won’t explode anymore.
Summing Up – Traveling With Hairspray
It’s hard to find a hairspray can that’s below 3.4 oz in size because most of them come in 9-12 oz containers. If you search for “travel size hairspray” on Amazon, you can find a few options that are below 3.4 oz. But they’ll last only for a few times, which means that if you’re going on a longer trip, you’ll need more than one bottle.
So the only real solution is to pack your regular, full-size hairspray in checked baggage. But because hairspray is cheap and you can buy it anywhere, you could also buy it at your destination. This way, you could leave some room in your hand baggage for other, more important, and more expensive toiletries, like your makeup.