The research reveals that 18% of 18-44 year olds, equivalent to 2.4 million people nationwide, are actively putting off having children because of high housing costs. This rises to 24% among 18-34 year olds.
One in five (22%) 18-44 year olds had waited for as long as six years to start a family, with over a third (37%) expecting housing costs to continue to delay their plans for another four years.
The figures come from a survey commissioned by the housing charity to discover the impact of the lack of affordable housing across all areas of people's lives. In particular, the research examines the impact on relationships and family life.
Kay Boycott, director of policy and campaigns at Shelter, said: "These figures show just how pervasive the housing crisis is. Whilst it is responsible to ensure that you can afford to support a new baby, it is completely unacceptable that housing costs are changing important life decisions like starting a family in such a significant way."
Meanwhile, the average age of a first time buyer without financial help from family or friends is now 37 years old, up from 33 in 2005.
Ms Boycott continued: "Housing affects so many areas of people's lives. In this election year, it's vital that all political parties make housing a top priority so that future generations can exercise choice in their family life.”