Energy giant npower has refused to reveal if it paid any UK corporation tax last year – despite making nearly £250million profit.
The firm has avoided paying the tax over the last four years by offsetting its investment spending.
Npower today revealed it made £246m supplying homes and businesses last year, up 1.4% on 2012.
But the company, owned by Germany’s RWE, dodged the question of corporation tax, claiming it would publish a tax report in the summer.
A spokesman said: “RWE has invested more than £5billion into new energy infrastructure for the UK in recent years, and all major parties support the use of capital allowances to encourage this kind of investment.
“However, this is not tax avoided, it is tax deferred.”
It came as npower boss Paul Massara denied last year’s profit was “excessive”. The firm, which has unleashed hundreds of job losses, made £134m from supplying homes, down from £141m in 2012, but profits from selling to businesses jumped nearly a quarter to £112m.