MORE than a million better-off families have lost some or all of their child benefit.
Families with one parent earning more than £50,000 lose part of their child benefit and it will be fully withdrawn where one parent earns above £60,000.
The government hopes to save £1.5 billion a year as a result of the changes.
David Cameron described the move as "fundamentally fair" but Labour said it was a "huge assault" on families.
The prime minister said: "I'm not saying those people are rich, but I think it is right that they make a contribution. If we don't raise that... from that group of people — the better off 15 per cent in the country — we would have to find someone else to take it from."
Shadow chancellor Ed Balls said the Government should tax the richest, rather than make changes that affect those on middle incomes.
Swansea East MP Sian James said her office was bracing itself for a deluge of inquiries about the changes.
The changes came in yesterday — the day before a Commons debate over the welfare system, when MPs were set to discuss plans to break the link between benefit rises and inflation.
Other changes set to come into force throughout the year will affect council tax benefit and housing benefit.