Flying into Lukla means that there are weight restrictions in what you will be able to carry with you, regardless if you are travelling independently or using a tour operator. Even though the weight varies slightly between different airlines it is normally 10 kgs (22 lbs) for the checked-in bag and 5 kgs (11 lbs) for the carry on. If you are using porters they will have their own maximum weight limits of around 10 kgs (11 lbs) per trekker.
Daypack: Here you will only carry what you need to have during the day: rain gear, extra clothes, drinking water and some snacks. This pack doesn´t have to be more than 40 L. I have the Haglöfs Mila Q 30. Osprey is also a good brand for bags.
Backpack/duffel bag: If you are travelling with a tour operator they will give you a duffel bag that will be carried by the porters. They are normally big enough to fit all the gear but it is very easy to come up to 10 kgs if you are taking a lot of extra things “just in case”. If you are travelling independently or want to leave your “normal” clothes at the hotel while you are travelling the The North Face duffel bag in size M is a really good choice.
Dry bags: When it rains water seems to get everywhere so you don’t want your camera, phone and documents to get wet. I bought two sizes of the Sea to Summit dry bags (1 L and 20 L). The big one is very useful to separate the wet clothes from the dry inside the tent and the smaller one is where you can put your phone and camera.
Raincover for the daypack: Some bags have a built-in raincover so if you have to buy a new one, those get some extra points, otherwise it can be bought separately.
I followed a simple layering principle and it worked well. There was no piece of clothing I wish I had brought nor something I didn’t use at all during the trek. I was never cold. This might vary from person to person. I tend to prefer cold weather but freeze easily, especially when resting or when standing still.
Waterproof jacket/Shell Jacket: We were a little bit unlucky with the weather and even though we never experienced any heavy rain it was very misty and humid in the air causing all your clothes/backpack to get wet. So a rain jacket and rain pants is a must. I used The North Face Women’s Resolve Jacket.
Insulation Jacket: It was never that cold to use a down jacket while trekking but it was good to have while walking around in the villages. I used Arcteryx Cerium LT with a hoody, it is extremely warm, light and very compressible. Something in this range is what I would recommend, no need for an expedition suit/jacket. Synthetic materials are of course a very good alternative to down, if not better.
Something to consider is that the jacket is hip-lenght at most. Longer than that will make strapping your backpack quite hard and it is uncomfortable for walking uphill.
Fleece: Fleeces come normally in three categories 100 (lightweight), 200 (medium) or 300 (heavyweight). I brought one lightweight and one mediumweight. It is possible to achieve the same warmth ratio by bringing three light ones (which is also a good option) or only one heavyweight (which I don’t think is a good choice). Layering doesn’t mean wearing as much clothes as possible but being able to remove/put on clothes easily when weather changes. If it gets warmer and you only have one heavyweight it will be very hard to remove some clothes while three thin fleeces can feel like wearing too many layers at times. But this is a personal preference.
Thick fleece: I love the Haglöfs Bungy II Q with hood (200). I use it all the time, both when hiking, climbing or as a stand alone inside the car during the winter. It is extremely warm and cosy. Definitely one of my best purchases.
Light fleece: For the lighter fleece I got the The North Face Women’s Glacier (100). Very good fleece also.
As of now I think both models are discontinued, but the newer versions (which might have a different name) are equally as great.
T-Shirt/Tank tops/Sports bra: Except for when it is really cold I wear only a normal t-shirt (not cotton) or sports tank top under the fleeces. The classic Nike, Adidas (or any other sports brand) tanks/t-shirts will do. For women any sports bra you like and that is comfortable can be used. The most important about this layer is that it is not cotton and that has wicking properties. How many of this you bring is a personal choice and how comfortable you are about using the same piece of clothing more than once. I wouldn’t bring more than one per day.
Base layer/thermal top: I got the Icebreaker Tech Top LS and it is AMAZING. I discovered this brand while investigating about base layers and I really love it now. This top is really thin and light but extremely warm on its own. It is a good piece of clothing to wear both when walking and also when just hanging around in the tent. I use it also to sleep. It is not cheap as it is 100% merino wool, but it is definitely a good investment.
Waterproof trousers: The ones I like are the both the Resolve or Venture pants from The North Face. Buy them a few sizes bigger since you might need to wear them on top of all your other clothes. It is also important that they have zippers at the end, to be able to quickly put them on without needing to remove your shoes.
Softshell pants: I only used this on summit day and when hiking at home in cold weather. I have the Haglöfs Rugged II Mountain pants. They are not supposed to provide protection from the rain but most soft shells are water-repellent, which is good. It is important that they are windproof, that they fit on top of all your other layers and that you get good mobility with them on. Gore-Tex or other similar materials are good for this layer.
Fleece pants: I have the Didriksons Alpi Fleece pants and are one of my best purchases. They are extremely warm and cosy so I have used them a lot, both when hiking but also when it is really cold at home and I am walking to the car/gym/grocery store. On the mountain they are very nice to walk with and also to have on while hanging around. I used them on colder days on top of my thermal tights or normal tights.
Hiking pants: For normal hiking conditions (this means not extremely cold and no rain) I used the The North Face Women’s Horizon Convertible hiking pants or normal training tights (the ones I use at the gym). I love wearing tights so I used them as much as I could, sometimes by themselves if the weather allowed it and sometimes under my fleece pants or this hiking pants. On colder days I used thermal tights instead.
Thermal underwear: I have the Icebreaker Vertex Leggings which are fantastic and really warm. This ones are amazing and definitely one of my best purchases. I use them to sleep together with my thermal top, under my hiking pants/fleece pants/softshell depending on how cold it is or as a standalone pair of tights.
The shoes are probably the most important part. Since getting blisters can really make your trip miserable I recommend buying the right size (big enough so you are going to be able to wear them with thick socks and still be able to wiggle your toes) and having walked with them at least for a few months prior to the trip in different types of terrain. Surprisingly a lot of people rent their hiking boots in Kathmandu but it is not something I recommend, there are a lot of cheap boots that have great quality. If you are very used to walking you can also use trail running shoes.
Hiking boots: They do not need to be very sophisticated though, normal trekking boots will work perfectly. No mountaineering/double boots/plastic boots are needed. They need to be comfortable to walk with, warm and waterproof. I made the mistake of buying my boots too early and having only summer/warm weather in mind, so when I bought my thickest mountaineering socks I realized that the boots didn’t fit with them on. Do not make the same mistake so have this in mind if ordering online and get at least one size bigger. There needs to be enough room to wiggle your toes while having your thickest socks on. I used the La Sportiva Trango Trek Micro Evo and I am really happy with them.
Socks: I brought one pair for each day in different thicknesses plus some normal regular socks. My thinnest pair was the Icebreaker Hike Lt Liner, very nice pair of socks, I really like it. They are ok warmth wise. For the medium thickness I had Smartwool’s Hike Medium Crew which is very comfortable and warm as well. I used them for summit day and for sleeping. The heaviest pair I have is the Icebreaker Mountaineer Heavy which is extremely warm and which I have never used except for sleeping.
Trainers/running shoes/etc: There is a lot o down time to hang around in the villages and it is good to have a pair o lighter and breathable shoes. They do not need to be very sophisticated, just something that feels light and comfortable.
Camelback/hydration pack: This is the best invention ever. I wish I could have one of this attached to my back all the time. This is why it is important that your backpack can fit one of those, it is really nice to be able to drink without stopping and without having to reach out for your water bottle. I have the 2 liter Platypus Hoser and I am happy with it, though it leaks a little bit sometimes. The water freezes on summit night so get an insulated tube as well.
Water bottles: I have two Camelbak Eddy bottles in 0,75 liters. Unlike a normal water bottle you can drink from it without having to tilt the bottle and your head backwards, you just sip from the built-in straw. This is very practical if you bicycle, since you can drink from a bottle without loosing sight of the road. The only downside with this bottles is the space they take in your pack when travelling so a good alternative would be the Platypus Soft Bottles. They are made of reusable soft plastic, weigh nothing and can be packed really small when you are not using them.
I personally feel handicapped and trapped while using gloves so I avoid them at all costs. I prefer using fleeces/shirts that have a thumb hole, or just pulling my sleeves over my hands. Sometimes it truly is too cold for that so I use the Arcteryx Gothic Gloves which are very thin and you can still do basic tasks with them like tying your shoelaces or eat.
It only gets extremely cold on summit night and I never made it to the summit during the night so my mittens didn’t get to be tested in the most extreme cold conditions. I had the Kombi Ryde II GTX which are regular mittens. No down/expedition mittens are needed unless you REALLY get cold in your hands.
I do not use hiking poles and that is why I get away with not using gloves most of the time. If you use poles then the Arcteryx ones will work for most of the trek but for the summit night you will need really warm mittens.
Sleeping bag: At night it gets COLD the higher up you go. I have the Marmot Womens Ouray which is 650+ fill power goose down, comfort temperature is rated at -10 C with a lower limit of -18C. It is specially designed for women. I would not recommend bringing something rated for temperatures higher than that, specially if the plan is to use it without a liner. This is an expensive investment and if the cost is an issue it is possible to hire one from your trekking company.
Sleeping bag liner: There are ways to make your sleeping bag a few degrees warmer and this is by using a liner. The Sea to Summit Thermolite Reactor increases your sleeping bag temperature by up to 11 C or the Thermolite Reactor Extreme which increases it up to 15 C. I have the first one. By using this it is possible to have a sleeping bag that is rated for 0 C and it might save you some money.
Fleece beanie: I used the Didriksons Skylar Beanie and I really like it. Any fleece beanie will work just fine though if you intend to use it by itself, with nothing underneath, make sure to get one that it is a bit tight-fitting and windproof. For the waterproof part you have your rain jacket with a hoodie.
Headband: I really love those when training outside in cold weather in general, so I use it by itself or under the beanie if it is really cold. I have a normal Nike running headband with fleece on the inside.
Balaclava: I have mixed feelings about this and I haven’t used mine, but a lot of people thinks is good to have on summit night. I would not recommend investing in a very expensive one though.
Buff: This is very nice to have and quite versatile since it can also be used as a headband. Any kind will work just fine.
Other useful things
Head torch: On summit night you walk in the dark and unless the sky is clear and you are climbing on full moon it can get pretty dark. No need to stress about which torch to buy, any will work just fine. It gets dark around 6.30 pm so it is good to have in your tent if you want to read or when going to the toilet in the middle of the night. (Bring a lot of extra batteries)
Books/Kindle/Reader: It gets dark and cold very early so there is not much to do while at camp. Books are very good company, specially if you are doing your trek alone. A notebook and a pen is also nice to have if you like to journal.
Camera/phone/mp3 player: Bring extra batteries for all of this, specially your camera. You don’t want to miss the opportunity to capture your glorious summit moment.
Snacks: Energy bars and gels are good to have. The food you get in the mountain is plenty and really good but it is a good idea to bring some of your favourite snacks. I would opt for high-quality products like nuts and whole grain cereal bars instead of candy and chocolate. The Trek’n’eat Peronin powder is a fantastic discovery. It is not to be used in normal circumstances but in cases in which your appetite is gone and your stomach has stopped digesting food because of the altitude the peronin doesn’t need to be processed by the body and is absorbed immediately. It gives an extreme boost of energy.
Walking poles: Personal preference, some people use them all the time and love them.
Power bank/solar charger.
Basic first-aid kit: Something like the Lifesystems Trek First Aid Kit will work just fine. Hopefully you will not need it but it is good to have.
Blister plasters: Compeed and Scholl make really good ones with different uses. Leukotape Sports tape can also do wonders.
Hydration sachets/electrolyte tablets: The name/brands might vary in different countries but anything that is intended to replace fluid and electrolytes in your body.
Acetazolamide (Diamox): It is a personal choice whether to use this to help with acclimatization or not. It can be used preventative and it is up to you to do your research and decide what is best. But it can also be used in emergencies and it can save your (or someone elses’s) life so I would recommend bringing it with you.
Other medications: I would not take anything that I don’t normally use at home (except diarrhoea tablets) nor something I haven’t tried before. No need to go overboard with this and bring the entire pharmacy. I only had some painkillers.