This research comes out today as Shelter highlights the lack of affordable housing in the UK.
The charity says "successive governments' failure to build enough affordable homes has left millions trapped in an unstable and expensive rental market".
For this study, Liverpool Economics modelled how long it would take for someone in their twenties to save for a deposit worth 20% of an average house, based on current and projected prices and the cost of living, in every county and borough in the country.
The projections are based on someone starting in September 2014 with no savings – illuminating how important inheritance and parental help is for first-time buyers.
Shelter found last year that parents of first-time buyers were ploughing £2 billion into the housing market, double what the government spends on building affordable housing.
Shelter's chief executive, Campbell Robb, said in a press release:
Homeownership used to be within most people's reach, but the rising shortage of affordable homes has pushed house prices up so high that for millions of young people it's now just a fantasy, however how hard they work or save.
Parents are right to be worried. The reality is that unless we get a grip on the housing shortage soon, children today could spend decades paying out dead money in expensive rents, or living at home well into adulthood with little hope of planning for their own families.