Fathers now have the opportunity to share time off
Many fathers are unaware of their paternity rights, according to the government as it starts a new awareness campaign for dads.
A small survey of 560 fathers found that a fifth were not sure whether their employer offered flexible working arrangements.
From April 2011, new mothers can transfer the second half of their year-long maternity leave to the father.
But a recent survey suggested many fathers could not afford the time off.
The law states that fathers are entitled to two weeks' paid paternity leave, paid at £123.06 a week, if they have at least 26 weeks' service with their employer by the 15th week before the baby is due.
Expectant fathers should tell their employer about taking paternity leave by the 15th week before the baby is due. They can take up to 13 weeks of unpaid leave until their child is five years old
Many businesses offer extra flexible working arrangements to fathers, which dads can request.
Now the government is running a month-long campaign with leaflets and posters explaining fathers' rights.
"We know that rights for dads at work are valued by people and that businesses also see real benefits in offering them, but our research shows that there are still some dads out there that are not aware of what they are entitled to and therefore risk missing out," said Employment Relations Minister Lord Young.
"Our campaign is all about making sure dads know what they can do and to help them have more confidence as they weigh up what works best for them and their family. The key is to talk to their employer."
In October, a Equality and Human Rights Commission survey found that almost half of working fathers did not take their right to two weeks' statutory paternity leave because they could not afford to.
The Commission said paternity pay should be increased from the statutory £123 a week to 90% of fathers' actual pay.
In January, the government announced a parents' leave plan that would mean if a mother returns to work, the father could take six months off with half of the period paid at £123.06 week.
The Conservatives said the plans, which were first set out in 2004, had been repeatedly postponed and trailed behind their own proposals.