What is the carry-on limit for mountain flights in Nepal like Lukla?

Bush plane flights to Lukla (LUA), Phaplu, Dolpo, and similar STOL airstrips operate a combined weight limit of 15 kg for all luggage — checked and carry-on together. This is a total weight limit, not a separate cabin allowance. Soft bags are required because the aircraft hold cannot fit hard-shell cases.

Do I need a soft bag for Nepal mountain flights?

Yes. Twin Otter and similar bush aircraft used on Nepal mountain routes require soft duffel bags or backpacks for both checked and carry-on luggage. Hard-shell suitcases physically cannot fit in the aircraft hold or overhead areas and will be refused at the gate.

What is Nepal Airlines' carry-on limit?

Nepal Airlines and Himalaya Airlines both enforce a 7 kg cabin bag limit on their international routes into Tribhuvan International Airport (KTM). The size limit is 55 × 35 × 20 cm for Nepal Airlines.

Should I rent trekking gear in Kathmandu or bring it from home?

For most items — trekking poles, sleeping bag liners, down jackets, crampons — renting or buying in Thamel (Kathmandu's trekking district) is cheaper than shipping gear from home and saves significant weight in your carry-on. Good quality rental gear is widely available at very reasonable daily rates.

What altitude medication should I carry in my bag?

Acetazolamide (Diamox) is commonly prescribed for altitude acclimatisation above 3,000 m. Carry it in your personal bag or carry-on, not in checked luggage. Ibuprofen for headaches, oral rehydration salts, and lip balm for extreme dryness are also worth packing in your cabin bag for immediate access.

Carry-On Only for Nepal: Pack Smart for Kathmandu and Mountain Flights

Nepal is one of the most demanding carry-on destinations in the world — not because of strict airline rules at Kathmandu's main airport, but because the mountain flights that reach trekking trailheads operate with hard limits that apply to your entire luggage, and they require soft bags. If you're heading to Everest Base Camp via Lukla, or flying to Pokhara or any high-altitude airstrip, your entire packing philosophy needs to start with the bush plane constraint.

Airline Carry-On Rules at a Glance

Route / Airline	Carry-on limit	Total luggage limit	Bag type
Nepal Airlines international	7 kg, 55 × 35 × 20 cm	Per ticket fare	Hard or soft
Himalaya Airlines	7 kg	Per ticket fare	Hard or soft
Kathmandu to Pokhara (domestic)	7 kg	20 kg total	Hard or soft
Mountain flights (Lukla, Phaplu etc.)	15 kg combined total	15 kg all-in	Soft bag REQUIRED

The critical number is 15 kg combined for mountain bush flights. That is your carry-on plus any checked bag added together. There is no separate carry-on allowance for these routes.

The Mountain Flight Rule: 15 kg Total, Soft Bag Only

Bush planes serving Lukla (Tenzing-Hillary Airport), Phaplu, Juphal, Dolpo, and other Himalayan STOL airstrips are almost always Twin Otters or similar small aircraft. They carry a maximum payload, and that payload includes you, your clothing, and all your bags.

The 15 kg all-in rule means:

Your day pack weighing 5 kg
Your trekking duffel weighing 10 kg
Total: 15 kg. You cannot exceed this.

The soft bag rule means:

Hard-shell suitcases are physically refused at Kathmandu domestic terminal check-in for mountain flights
A compact backpack (35–50 L) or a soft duffel that compresses is the correct bag
If you arrive at Tribhuvan International with a wheeled hard-shell case, you will be storing it at your Kathmandu hotel and repacking before the mountain leg

Plan around this from the start. Your international bag and your mountain bag should be the same bag, or you need a plan for storing non-mountain gear in Kathmandu.

Trekking Gear: Rent in Kathmandu, Don't Carry from Home

Thamel, Kathmandu's trekking district, is lined with gear shops selling and renting:

Down jackets (rent from around $2–5/day, buy from $20)
Sleeping bag liners
Trekking poles
Crampons and micro-spikes
Gaiters, balaclava, gloves
Waterproof jackets and trousers

Renting a down jacket in Kathmandu saves 500–800 g in your carry-on and is often better quality than what you'd buy at home for the same price. Buy or rent sleeping bag liners rather than full bags — most tea house lodges on the Everest and Annapurna circuits provide blankets.

What to bring from home rather than rent:

Your trekking boots (rent boots rarely fit well and blisters on altitude trails are serious)
Merino wool base layers (quality varies in Kathmandu rentals)
Altitude medication if prescribed (cannot be purchased easily on the trail)
Headtorch with spare batteries
Water purification tablets or filter

What to Pack in Your Carry-On (In-Cabin Items)

For mountain trekking trips, the cabin bag serves as your immediate-access pouch during the flight and your day bag on the trail:

Altitude medication (Diamox, ibuprofen, electrolytes)
Chapstick and hand cream — altitude air is extremely dry above 3,500 m
Sunglasses with UV protection (UV is intense at altitude)
Snacks for the bush plane and first day
Passport, permits (TIMS card, Sagarmatha National Park permit)
Cash in Nepali rupees — there are no ATMs above Namche Bazaar

Keep these items with you at all times. If your duffel is gate-checked on a bush plane, you still have what you need.

Clothing Strategy: Two Climate Zones

Nepal presents a packing challenge because Kathmandu and the lower Terai region are hot (25–35°C in summer), while the mountains above 3,500 m can hit -15°C at night at Everest Base Camp, and nights at Namche Bazaar (3,440 m) regularly drop below freezing even in October.

Base layers: 2 merino wool long-sleeve tops and 1 pair of merino long johns cover you from 3,000 m upward and pack small. Merino handles odour well for multi-day treks without washing.

Mid-layer: 1 lightweight fleece or synthetic puffy (rent a heavier down jacket in Kathmandu for high altitude).

Shell: 1 waterproof jacket (doubles as wind protection at altitude).

Lower body: 1 pair of trekking trousers that zip off to shorts — works for Kathmandu heat and mountain cold.

Footwear: Trekking boots on your feet to the airport. They are too heavy to pack.

Airport Tips: Kathmandu Tribhuvan (KTM)

Tribhuvan International Airport is a single-runway airport handling both international and domestic flights. International arrivals and departures are relatively organised; the domestic terminal for mountain flights is a separate building.

Security follows standard liquid rules on international flights
Domestic mountain flights depart early morning — weather closes mountain airports by late morning almost daily. Be at the domestic terminal by 6 am
Flight cancellations to Lukla are extremely common. Build at least 2–3 buffer days into your itinerary before any time-sensitive commitment (return international flight, work deadline)
On-arrival visas are available at KTM for most nationalities — the queue can be 30–60 minutes

Practical Tips

Never assume your mountain flight will operate. Lukla has one of the highest cancellation rates of any airport in the world due to cloud, wind, and visibility
Store your city clothes in Kathmandu. Most trekkers leave a small bag at their Kathmandu hotel while trekking and pick it up on return
Carry cash. Beyond Namche Bazaar, cash is the only payment option. Withdraw Nepali rupees in Kathmandu before the mountain leg
Altitude sickness is real. Ascend slowly — the standard recommendation is no more than 300–400 m of altitude gain per day above 3,000 m

Bottom Line

Nepal carry-on travel hinges on the mountain flight constraint: 15 kg total, soft bag only. Pack everything into a 35–50 L backpack or soft duffel, rent heavy trekking gear in Kathmandu, keep altitude medication in your cabin bag, and build buffer days around mountain flight cancellations. The flexibility of carry-on-only travel is especially valuable in Nepal, where changed plans are routine.