This is the first time the CPI has fallen over the year since official records began in 1996 and the first time since 1960 based on comparable historic estimates.
The largest downward contribution came from transport services - notably air and sea fares, with the timing of Easter this year a likely factor.
CPIH grew by 0.2% in the year to April 2015, down from 0.3% in March 2015.
A Bank of England report in February admitted that “it is now more likely than not that CPI inflation will dip briefly below zero at some point in the first half of 2015”.
In Mark Carney's open letter to George Osborne, published last week, the Governor admitted that it is "very likely that [he] will need to write further open letters in the coming months".
The Governor is required to write to the Chancellor if CPI inflation moves more than one percentage point above or below its 2% target.
Chancellor George Osborne said:
“Today we see good news for family budgets with prices lower than they were a year ago. As the Governor of the Bank of England said only last week, we should not mistake this for damaging deflation. Instead we should welcome the positive effects that lower food and energy prices bring for households at a time when wages are rising strongly, unemployment is falling and the economy is growing. Of course, we have to remain vigilant to deflationary risks and our system is well equipped to deal with them should they arise.”
Richard Pike, sales and marketing director of Phoebus software, commented:
"Today’s figures should probably be taken as “good-deflation” as lower prices at the supermarkets and the fuel pumps a few months ago are reflected. I don’t think we are entering a Japan “lost decade” scenario and I would expect to see inflation increase again moving forward.
"With wages now back above inflation at around 2%, consumers should continue to spend and this will only be good for the economy. What will be interesting will be whether the Government sets the benefits review as it does usually in April based on this deflationary figure as this could in theory mean cuts in some benefits."
