"You will not find a country anywhere in the world that is more open to technology, more open to investment and more open for business. We're putting in place the right vision and the right policies to help your company succeed right here in the UK.
"That's why the world's leading technology companies are beating a path to our shores. And that's why we will continue to do everything we can to help technology investors and entrepreneurs invest, innovate and succeed in the UK."
Mr Osborne said the Government was "leading the world" in supporting technology companies and claimed ministers were pulling out all the stops to ensure the globe's top technology investors had everything they need to succeed in Britain.
The Chancellor said the Government was making "bold changes" to the tax system, pointing to the 5p cut in the top rate of income tax from 50p to 45p announced in March's Budget. He added: "We have introduced the most generous early-stage investment tax breaks in any country in the world."
London mayor Boris Johnson said: "It's fantastic that more and more companies are taking advantage of the enormous benefits of doing business in London, and I am delighted to welcome these new additions to Tech City."