Accomodation for theatre mini-breaks

If it's outside of term times I always stay at one of the LSE properties.
Mostly small rooms with shared bathrooms, but some properties have en-suites and apartments.All except the apartments have breakfast included.
Grosvenor House & Northumberland House suites are closest to the West End, but the most expensive.
Passfield House is on Tavistock Square and quick walk to Euston or bus stops for Trafalagar Square, Waterloo or Victoria buses.

YHA Hostel at St Pauls is fine, but you need earplugs for the bells! And the single rooms are at the very top of the house via many, many stairs.

all your options are too posh for my budget (well maybe except for the hostel ones). Airbnb is the choice! 250GBP for 10 days for staying in a room near Hammersmith. Yes, shared amenities. But a room where you can sleep alone and no one snores interrupting your sleep!
It is still pricey for me but this is the best I can afford and sleep alone in the room and live 30 minutes from all the WE theatres

Premier Inn is always consistent, comfortable and purple.

Holiday Inn not too bad, the free breakfast is yuck, even for free.

Travelodge, last time I stayed there, the bed gave me chronic backache.

Marriott, can be expensive, but the quality is excellent, American know how to do good hotels, (Travelodge aside) there ones are better than ours.

That breakfast is amazing value for money, I love it - and luckily they start serving at 7am even on Sundays, so I can take advantage of it before heading over to St. Pancras for my train home.

I LOVE pod hotels. I wouldn't want to spend a two week holiday in them, but honestly if I'm just putting my head down for a night, all I need is a bed, a ceiling, and a lockable door, and a pod hotel is just such a neat use of space. And with a location as hilariously as convenient as St Martin's Lane, I don't quite get why you would go for the hotel breakfast when the whole of central London is at your feet!

Well don’t know what price you paid but usually those Hub hotels go for £40-80 which comparatively to the areas is an utter steal. And being Premier Inns I feel far safer there than say a hostel or air bnb of similar pricing

I have to echo the votes for Premier Inn - unless I'm combining a business trip (and so getting accommodation on my company's expense account!), Premier Inn is the one I'll consistently choose. The one near Euston station (there's another just a few minutes walk away towards Kings Cross on Euston Rd) is fantastic. The staff are brilliantly friendly - not the most usual occurrence in London, I've found - and the breakfast (with discount vouchers) is great value.

Another person mentioned it, but it's worth saying - look at hotels located in the City or Docklands, if you want to get a weekend bargain compared to their weekday rates. Those business centric hotels are pretty much deserted by Friday night, and heavily discount their rooms pretty regularly. Slightly more expensive than the budget chains, but I've had a 5-star hotel room for just £20 more than a budget hotel! My favourite is the Grange hotel chain - there's one near St Pauls cathedral that has a separate 'aparthotel' block just down the street. Really lovely studio room, with a mini kitchen (very useful) and easy walking distance from various tube routes, as well as bang in front of the cathedral, so plenty of eating options!

I think the Hub breakfast does vary with the location. I stayed at the one in Edinburgh and it was quite a small spread in the bar with a coffe machine and pastries.

LSE Bankside is my "go to" place at the moment. Nice walk along the river and a choice of bridges to get to the theatre district. Really convenient for the National, Menier, Union, Old/Young Vic and a few others. And next to the Tate Modern if that's your thing.

I've tried many of the other halls around London. Some others are okay, but that one wins out on price and location terms. The bathrooms are shared between two rooms at most (sometimes you get an en-suite) and there is a very good buffet breakfast.

Will be a shame when term starts soon and they're no longer available.

I'm currently working part of the week in London, but not enough days to move to London, so getting very familiar with the cheap options and how to make the most from them (the chain hotels just don't tend to price up as an option - although there can be good deals in the Docklands - and Croydon is direct on the train to the Victoria theatres if you're seeing Wicked, Hamilton or going to The Other Palace).

There are also lots of very cheap hotels around Earls Court, which is just a few stops from the West End. Most of them are fine if you understand you're getting a small room which won't have had much money spent on repairing it and you just need somewhere to sleep. Earls Court is great for food and small supermarket options. With those, look at reviews to avoid the very worse, but take moans from people who don't understand what to expect from cheap hotels with a pinch of salt. I'd recommend checking for a private bathroom (some of those hotels only have about 1 bathroom per 20 guests - and lots of stairs to get to it and find it engaged) and don't assume any relationship between price and quality. There's very little between the £40 a night hotels (which might just be reduced as they have spare capacity that night) and the £100 a night hotels. You'll also often find a better deal if you're willing to change hotels based on which is cheapest on any given night (for Earls Court, I think it's a good idea not to stay more than 2-3 nights at the same hotel anyway - as at least then you're likely to get clean bed sheets).

Final hint. Chain hotels, if you stay enough, get status with them and book direct for all kinds of perks. You can also get status and free nights (to use at a luxury hotel) by taking out credit cards. 

Non-chain (lower end) hotels. These always seem to end up cheapest booking through one of the main hotel sites. You can often get cashback and extra discounts too. I mostly use Hotels.com as it has a very good rebate scheme (works with many of the university halls as well, including the LSE ones), but you can sometimes save a bit more by checking the price aggregation sites.

[disregard much of this advice if you're going for a romantic weekend - as opposed to just wanting somewhere acceptable and private to crash between shows/work etc]

Do Premier Inns/Travelodges tend to have minibar fridges?

You’ll be lucky to get a shortbread biscuit on the hospitality tray!

No. Travelodges definitely not, Premier Inn I'm not sure but I don't think so. 

Travelodge is super-no-frills with minimal services (very cheap soap/shower gel/shampoo), free wifi limited to 30 minutes per day, no safe for valuables and just a few open hangers for your clothes. Once you know what to expect, you can prepare though, i.e. I make sure to take an extra lock for my suitcase to lock up my valuables when I leave the room and bring all my own toiletries. Premier Inns don't offer that much more, but the rooms feel a bit nicer/bigger/more upmarket and at least outside London they usually have a bath tub. 

As a foreigner I love the British obsession with tea as even the Travelodges come with a small kettle for coffee and tea (great for a first cup of coffee in the morning before I get going). The kettle is the one thing I miss at the Hub.