How to visit London on Budget?

Hate to say this, but avoid London if you are on a budget. The place is mad expensive.

Your biggest cost is likely to be hotels.

Google for backpacker places as they are generally the cheapest.

The downside is you are far more likely to be a victim of crime in cheaper areas of the city.

Mugging is the big one, commonly committed with a knife.

Keep your phone and cash out of sight.

I think you can relax a bit more than Fred suggests

You don't say how long you will be in London for or what your interests are so it's hard to say.

But in terms of accommodation, other than hostels, have a look at the budget hotel chain Travel Lodge. You should be able to find a central location for about £50 a night.

On Time Out or Secret London you can find a lot of top free things to do in London lists.

There're various passes available for tourists as well as various offers and discounts available on everything really e.g. Today Tix for theatre, but again, you don't say what you're interested in.

Walk and take the bus rather than using the tube. It's cheaper and you will see a lot more.

There're a lot of affordable set menus especially at lunch. Even high-end restaurants offer them. Also have a look at Open Table and pick up food from supermarkets.