The wealth of your parents has more influence on earnings in Britain than in any other advanced country, according to a study.
Analysis by the Trades Union Congress (TUC) found only Italy had a similar level of "earnings persistence" through generations.
The report - Dismantling the Barriers to Social Mobility - compared the UK to other major economies on seven key criteria.
They included income equality, where Britain ranked 29th out of 34 Organisation for Economic Cooperation and Development (OECD) states.
It came 14th out of 29 countries in Unicef research on the proportion of children living in households with below 50% of median income.
For full-time women's employment, the UK was only 21st out of 26 wealthy nations.
But it was above average in per capita spending on education.
TUC general secretary Frances O'Grady said: "People's incomes in Britain are more influenced by their parents' wealth than in any other advanced country.
"This lack of social mobility holds millions of people back and means that they don't get a fair share of the benefits of a growing economy, such as decent pay and educational opportunities.
"Worse still, rising inequality means that the price people pay for a lack of social mobility is getter bigger.
"But while few people in this country would argue against social mobility, successive governments have a poor track record of tackling it.
"When it comes to income inequality and full-time employment rates for mothers, the UK is ranked well below our global competitors.
"Raising the full-time employment rates for mothers is an important way to boost social mobility and one we'd like all political parties to commit to.
"But with over six million people working part-time in Britain we also need to tackle the pay and career penalties faced by those who want - or need - to work shorter hours."