The map, created by reallymoving, allows prospective homeowners to search for properties by budget and number of bedrooms.
It highlights the areas with the greatest choice of properties for first-time buyers.
The data suggests that those searching in and around London should head east, with 12 of the top 20 most affordable locations found in east London, Essex, and Kent.
The RM13 postcode in Rainham and RM6 postcode in Romford, including Chadwell Heath, rank joint-eighth in the list.
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With a budget of £420,000, which is the average purchase price for a first-time buyer purchasing a two-bedroom property in Greater London, 90 per cent of two-bedroom properties in the postcodes are affordable for first-time buyers, according to researchers.
For those with a budget of £315,000, which is typically spent on a one-bedroom property, 96pc of homes in the two postcodes are within reach.
Rob Houghton, chief executive of reallymoving, said: “If first-time buyers focus only on average house prices, the dream of owning a home may seem like an impossible task, but those numbers don’t tell the full story.”
The map is available on the reallymoving website and is free to use.
