From onesies to thongs: The 12 things flight attendants say you should never wear on a plane.

You know who always looks great making their way through airport terminals? Celebrities. Obvs. 

The high heels. The tight leather pants. The oversized faux fur coat. The statement glasses. Etc, etc.

Yet, while we'd all love to replicate these fancy wardrobes for ourselves and look our very best hopping on or off a plane, the fact is that some (most) of these trendy ~lewks~ are best left in your checked baggage.

Watch: Here's your horoscope at the airport. Post continues below.

So, what are the 'rules' when it comes to travel attire? What shouldn't you wear on a flight??

Well, from what we've learnt, it's one thing to dress for comfort, and another to dress to be upgraded.

Flight attendant Katie Ellen told Mamamia, "On international flights, if we have spare business seats to upgrade regular Joes, we would be instructed to upgrade the well-dressed and well-heeled."

But when it comes to safety, comfort and practicality – things are a little... different.

So, we asked some frequent flyers and flight attendants exactly what to NEVER wear on a plane. Here's what they said.

1. Jeans.

"I'm a flight attendant and previous ground crew. The swell is real. You can start the day with a flat stomach and by the time you reach the other side, you have a swollen gut. Some people find jeans help with swelling - others, not so much." – Katie.

"Never wear jeans, especially if your legs swell in the air. You might have seam lines on your legs for a few days." –  Maggie.

"For long haul international flights, I always wear pants with an elasticised waistband, as 24 hours in the air can play havoc on your digestive system, so you may need room for bloating." – Trish.

2. Compression pants or tights.

"Never wear compression tights! I did this once and my feet swelled up soooo much. I got confused between compression pants and compression socks. It was painful." – Mary.

"I would only wear tights as an emergency and if they are 100 per cent natural fibre. Garments too tight to the vagina are not good when you're sitting for a long time. There's no breathing room!" – Claudia.

3. Knee-high boots, high heels or thongs.

"Don't wear knee-high boots because they won't fit in your suitcase. Your legs will swell up and you won't be able to get them back on if you take them off for a sleep on your 12 hour flight. Easy on and easy off shoes win every time!" – Caroline.

"My father is a pilot and always has instilled in me to only wear flat, enclosed shoes. He always tells me, 'If the plane crashes, you don't want to cut/burn your feet and you may need to run away!' I cringe when I see people wearing thongs on a plane." – Emily.

"Never wear high heels. It's even mentioned on airline security videos (the boring video they show you before taking off). The logic behind it is you can't run or slide down the emergency landing slide in case you have to!" – Devjanee.

4. A onesie or overalls.

"Never wear a onesie! Going to the toilet will be a nightmare, and the top half that you've had to strip off will fall in whatever gross stuff is on the floor in the toilet." – Fiona.

"I saw someone in a fitted onesie recently on a 15 hour flight and it didn't look very comfortable!" – Sinead.

"No jumpsuits. The pee complexity in a tiny airplane bathroom is too much!" – Courtney.

5. Socks.

"I'm a regular UK-Aus flyer pre-COVID. Always. Wear. Shoes. Do not leave your shoes off when you're walking around the cabin." – Emma.

"Never wear socks into the lavatory. Put your shoes back on!" – Katie.

6. A prosthetic leg.

"I wore my prosthetic leg from Melbourne to Sydney and my stump swelled, it was awful! Definitely recommend putting any detachable limbs in your luggage!" – Bianca.

7. Wide-legged trousers.

"Wear pants/trousers with an elasticated or close-fitted hem. You don't want anything touching the floor of the toilet (or the floor anywhere, for that matter)." – Kerstin.

8. Underwire bras.

"Underwire bras are a big no from me. My overseas travel is usually 26 to 36 hours long (with layover), so I'm always prepared for the worst." – Claudia.

"I only ever wear sports bras or no wire bras." – Emma.

9. Flowy skirts.

"Never wear flowy skirts with elastic waistbands – they get caught in the seat and completely dak you when you stand up." – Gemma.

10. Ear buds.

"Ear buds are not the best because they don't allow circulation and ears need to pop!" – Claudia.

11. An ear loop face mask.

"I've just done a long haul flight from South Africa and my ONE piece of advice is to wear a face mask that ties over your head and behind your neck - not the usual one that loops behind your ears. They are a killer after a few hours!" – Lara.

12. A wedding dress.

"I'm a flight attendant. Wearing your wedding dress to the airport will 100 per cent make sure you don't get an upgrade!" – Katie.

What do you avoid wearing to the airport? Share with us in the comment section below.

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