FXGuide.com claims £1 million UK
To build the futuristic world required the film makers to not only create believable robot killing machines, but environments and vast amounts of vfx just to hide the present day world. Typically, a low budget production is shot quickly to keep down costs and has limited production design and access to expensive locations. This film demanded exotic locations, long lingering CG shots - and all on a total budget of just one million pounds.
"We started our visual effects company Bandito VFX back in 2002 with one sole aim, to build a company that could make quality VFX for our first film" explained Gomez. In reality it took ten years before the film was started, and to pay the bills Bandito primarily does vfx for the episodic TV market. Even throughout the entire film's production, Gomez and Bandito had to continue to work on TV effects to pay the bills.
To put that into perspective, that's about the cost of each of the films, The Rise of & The Fall of the Krays - which had almost no vfx.